Official Factorio Wiki - User contributions [en]

Tutorial:Localisation

2026-06-10T11:37:49Z

Osmo: /* Default Behavior(s) for finding an Unspecified Localised String */ Improve this whole section, add rules for recipes and technologies. Remove "and is not an empty table" because empty tables are not valid localised strings (at least anymore).

{{Languages}}Mods should define human readable names for prototypes that they add. They can also define descriptions for items or custom strings for usage in GUIs etc. This is called '''localisation'''.

== File format ==
Translations are stored as .cfg files, with the following format:

<pre>welcome-message=Hello world
[category]
title=Category related title
# Comment
; Another comment</pre>
Any whitespace after or before <code>=</code> is included in the key or string, so <code>title =Category related title</code> will give an unknown key error if you are looking for the <code>title</code> key, since it is the <code>title </code> key.

<code>category</code> can be one of the existing locale categories, which permits implicit search mechanisms to find translations, but may also be another key, such as <code>[my-mod-messages]</code>. These are accessible the same as other translations, e.g. <code>{"my-mod-messages.hello"}</code>

These files are located within the language code of the language in the locale folder of the mod, so as an English example <code>__mod__/locale/en/any_name_here.cfg</code>. There can be more than 1 file per language, all of them will be read.

== Localising simple strings ==
The simplest localisation is of items, entities etc. If we say the item is <code>iron-plate</code>, the game will then search all loaded locale files for <code>item-name.iron-plate</code> and <code>item-description.iron-plate</code>, which in the locale file looks like this:

<pre>[item-name]
iron-plate=Iron plate
[item-description]
iron-plate=A plate made of iron.</pre>
If found in the locale, the label is set to this string. If not found, the game will instead show: <code>Unknown key: "item-name.iron-plate"</code>

In script, the localised string is formatted as <code>{"category.name"}</code>, so <code>game.print({"item-name.iron-plate"})</code> prints ''Iron plate''.

It is possible to use [[rich text]] features in the localised text if the location where the text is shown supports it, e.g. in the chat, prototype names and prototype tooltips.

<code>\n</code> can be used for line breaks if the location where the text is shown supports multiline text.

The list of all localization categories used by the base game is:

{| class="mw-collapsible mw-collapsed wikitable"
|-
!Localization categories
|-
|<code>[achievement-description]</code>
|-
|<code>[achievement-name]</code>
|-
|<code>[ammo-category-name]</code>
|-
|<code>[autoplace-control-names]</code>
|-
|<code>[controls]</code>
|-
|<code>[damage-type-name]</code>
|-
|<code>[decorative-name]</code>
|-
|<code>[entity-description]</code>
|-
|<code>[entity-name]</code>
|-
|<code>[equipment-name]</code>
|-
|<code>[fluid-name]</code>
|-
|<code>[fuel-category-name]</code>
|-
|<code>[item-description]</code>
|-
|<code>[item-group-name]</code>
|-
|<code>[item-limitation]</code>
|-
|<code>[item-name]</code>
|-
|<code>[map-gen-preset-description]</code>
|-
|<code>[map-gen-preset-name]</code>
|-
|<code>[mod-description]</code>
|-
|<code>[mod-name]</code>
|-
|<code>[modifier-description]
|-
|<code>[programmable-speaker-instrument]</code>
|-
|<code>[programmable-speaker-note]</code>
|-
|<code>[recipe-name]</code>
|-
|<code>[shortcut-name]</code>
|-
|<code>[story]</code>
|-
|<code>[string-mod-setting]</code>
|-
|<code>[technology-description]</code>
|-
|<code>[technology-name]</code>
|-
|<code>[tile-name]</code>
|-
|<code>[tips-and-tricks-item-description]</code>
|-
|<code>[tips-and-tricks-item-name]</code>
|-
|<code>[virtual-signal-description]</code>
|-
|<code>[virtual-signal-name]</code>
|}

== Localising with parameters ==
For more complex strings, localisation parameters can be used. For instance we want to show ''Time left: 10 minutes.''

So a key with a placeholder is defined, which is replaced by the first parameter after the locale key.:

<pre>time-left=Time left: __1__ minutes.</pre>
So it is used like this:

<syntaxhighlight lang="lua">game.print({"time-left", 10})</syntaxhighlight>
It also works with multiple parameters:

<syntaxhighlight lang="lua">game.print({"time-left", 10, 45})</syntaxhighlight>
<pre>time-left=Time left: __1__ minutes and __2__ seconds.</pre>
Which results in ''Time left: 10 minutes and 45 seconds.''

=== Built-in parameters ===
For some situations, we use localisation to show control schemes. For instance we want to say:

<pre>technology-prompt=Use T to open the technology screen</pre>
However the player may have rebound the key, but we can’t figure out which key as it would not be deterministic. So instead we use the built-in replacement functionality

<pre>technology-prompt=Use __CONTROL__open-technology-gui__ to open the technology screen.</pre>
We can also use this for items and entities:

<pre>big-iron-plate=Big __ITEM__iron-plate__</pre>
<pre>tiny-gun-turret=Tiny __ENTITY__gun-turret__</pre>

==== List of built-in parameters ====
<code>name</code> is the name of an internal game control or a prototype name, depending on context. <code>n</code> can be 1 or 2, it's used in parameters that control [[#Localising_alternate_input_names|alternate input names]]. For a list of internal game control names, see [https://lua-api.factorio.com/latest/types/LinkedGameControl.html CustomInputPrototype::linked_game_control].
* <code>__CONTROL__name__</code> - The combination of modifiers and input, such as "Control + Alt + Left-click", or "Not set".
* <code>__CONTROL_MODIFIER__name__</code> - The modifiers, such as "ControlShift", or, "No modifier selected."
* <code>__CONTROL_STYLE_BEGIN__</code>
* <code>__CONTROL_STYLE_END__</code>
* <code>__CONTROL_LEFT_CLICK__</code> is replaced with <code>control-keys.mouse-button-1</code> or <code>control-keys.controller-b</code>[https://crowdin.com/project/factorio/discussions/214]
* <code>__CONTROL_RIGHT_CLICK__</code> is replaced with <code>control-keys.mouse-button-2</code> or <code>control-keys.controller-x</code>
* <code>__CONTROL_KEY_SHIFT__</code> is replaced with <code>control-keys.shift</code> or <code>control-keys.controller-leftshoulder</code>
* <code>__CONTROL_KEY_CTRL__</code> is replaced with <code>control-keys.control</code> or <code>control-keys.controller-rightshoulder</code>
* <code>__ALT_CONTROL_LEFT_CLICK__n__</code> is replaced with <code>control-keys.mouse-button-1-alt-n</code> or <code>control-keys.controller-button-alt-n</code> (with parameter <code>control-keys.controller-b</code>)
* <code>__ALT_CONTROL_RIGHT_CLICK__n__</code> is replaced with <code>control-keys.mouse-button-2-alt-n</code> or <code>control-keys.controller-button-alt-n</code> (with parameter <code>control-keys.controller-x</code>)
* <code>__ALT_CONTROL__n__name__</code>
* <code>__CONTROL_MOVE__</code> - The Movement keys, squished together. Example: "WASD", from a conventional QWERTY English keyboard.
* <code>__REMARK_COLOR_BEGIN__</code>
* <code>__REMARK_COLOR_END__</code>
* <code>__ENTITY__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/EntityPrototype.html EntityPrototype] subclass.
* <code>__FLUID__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/FluidPrototype.html FluidPrototype].
* <code>__ITEM__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/ItemPrototype.html ItemPrototype] or subclass.
* <code>__PLANET__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/SpaceLocationPrototype.html SpaceLocationPrototype] or subclass.
* <code>__TILE__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/TilePrototype.html TilePrototype].

=== Plurals ===
Pluralization can be used in any string that uses a parameter (e.g. __1__) that is numeric, so something like an amount of minutes. It can be used multiple times per string.

<pre>format-days=__1__ __plural_for_parameter__1__{1=day|rest=days}__</pre>
This results in "1 day" and "2 days" / "500 days" etc.

The number after <code>__plural_for_parameter__</code> denotes which parameter is used to determine the plural. This is the parameter 1 in the above example. Anything inside the {} is used to make the plural. Each plural form is separated by a |.
The text in front of the = determines for what the plural form is used. Options for this are:
* A simple number, e.g. "1".
* Multiple numbers, e.g. "2,3,4".
* What the number ends with, e.g. "ends in 11" or "ends in 1"
* Multiple ends with, e.g. "ends in 1,ends in 2,ends in 12".
* "decimal" for any number with a fractional part.
* "rest" to give the default plural.

For negative numbers the plural is picked as if the number was positive, so a plural like <code>__plural_for_parameter__1__{1=day|rest=days}__</code> will result in "-1 day" for -1. 
For numbers with a SI prefix the plural is picked as if the number was fully written out, so a plural like <code>__plural_for_parameter__1__{1=day|1000=eons|rest=days}__</code> will result in "1k eons" for 1k.

Plural forms may be empty or contain other keys such as __1__ or spaces. This allows rather large plural forms:

<pre>__plural_for_parameter__1__{1=__1__ player is|rest=__1__ players are}__ connecting</pre>

The system picks the first fitting plural that it encounters when multiple would fit:
<pre>__plural_for_parameter__1__{ends in 12=option 1|ends in 2=option 2|rest=option 3}__</pre>
This will result in "option 1" for 12 and in "option 2" for 22 and in "option 3" for numbers not ending with 2.

The parameter used for pluralisation does not need to be present in the string. For example, a parameter could represent the number of list items present in another parameter:
<pre>
I like __plural_for_parameter__1__{1=only one thing:|rest=these things:} __2__
</pre>
Can result in "I like only one thing: trains", or in "I like these things: trains and turtles".

=== Concatenating localised strings ===
The special locale key: <code>""</code> is used to concatenate, as the table format does not support concatenation:

<syntaxhighlight lang="lua">game.print({"", {"item-name.iron-plate"}, ": ", 60})</syntaxhighlight>
Will result in: ''Iron plate: 60''

=== Advanced concatenation and modification existing localised strings ===

When working with LocalisedString tables in prototype definitions (e.g., in data.lua, data-updates.lua, or data-final-fixes.lua), there are several important rules and practical patterns:

'''All parameters must be strings'''

At the prototype data stage, every parameter passed to a localised string must be a string. Numbers, booleans, or other types will cause a Value must be a string error.

<syntaxhighlight lang="lua">-- This will cause an error:
localised_description = {"description.example", 42}

-- Correct:
localised_description = {"description.example", "42"}
-- or using tostring():
localised_description = {"description.example", tostring(42)}</syntaxhighlight>

This applies to numeric values from prototype properties as well:
<syntaxhighlight lang="lua">-- Wrong:
localised_description = {"description.radar-range", prototype.max_distance}

-- Correct:
localised_description = {"description.radar-range", tostring(prototype.max_distance)}</syntaxhighlight>

'''Appending lines to existing descriptions'''

When modifying a prototype that already has a localised_description (e.g., from another mod), use the <code>""</code> (empty string) key for concatenation with newline separators. Here is a practical function that safely appends a new line while preserving existing content:
<syntaxhighlight lang="lua">
local function append_localised_line(target, new_line)
if not target.localised_description then
target.localised_description = new_line
return
end

local result = {""} -- concatenation key
local idx = 2

local function flatten(desc)
if type(desc) == "string" then
result[idx] = desc
idx = idx + 1
elseif type(desc) == "table" then
-- Skip the key if present
if desc[1] == "" or desc[1] == "?" then
for i = 2, #desc do
flatten(desc[i])
end
else
result[idx] = desc
idx = idx + 1
end
end
end

flatten(target.localised_description)
result[idx] = "\n"
idx = idx + 1
result[idx] = new_line

target.localised_description = result
end

-- Usage:
append_localised_line(radar_prototype, {"description.radar-range", tostring(range)})

--Examples of modifying existing localised strings

--Example 1: Adding line if localised_description == nil
local entity = data.raw["assembling-machine"]["assembling-machine-3"]
append_localised_line(entity, {"description.building-size", "3.0", "3.0"})
--Result:
-- entity.localised_description = {"description.building-size", "3.0", "3.0"}

--Example 2: Adding a second line
append_localised_line(entity, {"description.max-health", "500"})
--Result:
-- entity.localised_description = {
-- "",
-- {"description.building-size", "3.0", "3.0"},
-- "\n",
-- {"description.max-health", "500"}
-- }

--Final in-game display (with localization):
--Size: 3.0x3.0
--Max health: 500
</syntaxhighlight>

'''Error interpretation'''

When a LocalisedString error occurs, note that the property tree error messages use 0-based indexing, while Lua tables use 1-based indexing. An error pointing to '''[2][1]''' refers to the element at index '''3''' in your Lua table, then its element at index '''2'''.

=== Localising alternate input names ===

In the introduction campaign, a special locale system is used for informing players how to do certain actions with their mouse.
The normal form is to use eg:
<pre>how-to-build=Use __CONTROL__build__ to place a building</pre>
which results in "Use Left mouse button to place a building". A more natural phrasing would be "Left-click to place a building", which can be achieved by using the following:
<pre>how-to-build=__ALT_CONTROL__1__build__ to place a building</pre>

These "alt" versions are controlled by a few special locale keys, mouse-button-X-alt-1 and mouse-button-X-alt-2. In English, form 1 produces eg "Left-click", and form 2 produces eg "Left-clicking". Only two alt forms ("1" and "2") are available at the moment, but if this a problem for some languages, more forms may be added in the future.
Extra mouse buttons, mouse scroll and keyboard keys are handled through the mouse-button-n-alt-1/2, mouse-wheel-alt-1/2 and keyboard-alt-1/2 keys, which just take the normal name and prepend something like "Press/Pressing", or "Scroll/Scrolling".

When translating to another language, you can use whatever forms you want here, but the important part is that you are consistent when you use the alt-forms everywhere else. It does not necessarily make sense to just copy the usages of alt forms from the English locale, and for some languages it may be more natural to simply not use this system at all.

== Accessing the localised result in code ==
While usually unneeded, it is possible to read the resulting localised text in code, for example to search in localised names.

See
[https://lua-api.factorio.com/latest/classes/LuaPlayer.html#request_translation LuaPlayer::request_translation],
[https://lua-api.factorio.com/latest/classes/LuaPlayer.html#request_translations LuaPlayer::request_translations] and
[https://lua-api.factorio.com/latest/events.html#on_string_translated on_string_translated event].

== Default Behavior(s) for finding an Unspecified Localised String ==
If a localised_name or localised_description is not defined in the prototype, Factorio may have a default search behavior.

Note: the angle brackets are meant to mean a generic term, they are not part of the actual string.

For most types, the name defaults to {"<base type>-name.<prototype name>"}, for example {"entity-name.underground-belt"}

Similarly, the description defaults to {"<base type>-description.<prototype name>"}, for example {"entity-description.underground-belt"}

Base types are represented by [https://lua-api.factorio.com/latest/concepts/IDType.html IDType].

=== Items ===
For items, the process is more complicated.

Note: place_result and placed_as_equipment_result are strings, and and Factorio fetches the matching prototype to examine.

# if localised_name is provided in the item prototype, use the provided value
# else if there is a place_result and it has a localised_name, use the localised_name of place_result
# else if there is a place_result, use {"entity-name.<place_result name>"}
# else if there is placed_as_equipment_result and it has a localised_name, use the localised_name of placed_as_equipment_result
# else if there is placed_as_equipment_result, use {"equipment-name.<place_as_equipment_result name>"}
# else use {"item-name.<item name>"}

Descriptions of items are found in the same way, except localised_description is used instead of localised_name and <base type>-description is used instead of <base type>-name.

Example: The transport-belt item does not have a localised_name, so 1->2.
There is a place result, but the entity prototype does not have localised_name set, 2->3.
There is a place result, so use the localised string {"entity-name.transport-belt"}.

Reference: [https://forums.factorio.com/viewtopic.php?p=494243#p494243]

=== Recipes ===
# if localised_name is provided in the recipe prototype, use the provided value
# else if main_product is set to an empty string: "", use {"recipe-name.<recipe name>"}
# else if main_product is set or recipe only has a single product:
#:# if the main product or only product has the same name as the recipe, use the localised name of the product. For item products, this uses the rules described in [[#Items]].
#:# else use {"recipe-name.<recipe name>"}
# else use {"recipe-name.<recipe name>"}
Descriptions of recipes have no special rules.

Reference: [https://lua-api.factorio.com/latest/prototypes/RecipePrototype.html#main_product]

=== Technologies ===
If localised_name is provided in the technology prototype, the provided value is used.
Otherwise, if the name of a technology ends with -<number>, that number is ignored for localisation purposes.
E.g. if the name is technology-3, the localised name defaults to {"technology-name.technology"} and the localised description defaults to {"technology-description.technology"}.

Reference: [https://lua-api.factorio.com/latest/prototypes/TechnologyPrototype.html#name]

== See also ==
* [https://lua-api.factorio.com/latest/types/LocalisedString.html LocalisedString data stage doc]
* [https://lua-api.factorio.com/latest/concepts/LocalisedString.html LocalisedString control stage doc]

[[Category:Modding]]

Tutorial:Localisation

2026-06-08T12:35:37Z

Osmo: Undo revision 218718 by Osmo (talk) since it was prematurely saved

{{Languages}}Mods should define human readable names for prototypes that they add. They can also define descriptions for items or custom strings for usage in GUIs etc. This is called '''localisation'''.

== File format ==
Translations are stored as .cfg files, with the following format:

<pre>welcome-message=Hello world
[category]
title=Category related title
# Comment
; Another comment</pre>
Any whitespace after or before <code>=</code> is included in the key or string, so <code>title =Category related title</code> will give an unknown key error if you are looking for the <code>title</code> key, since it is the <code>title </code> key.

<code>category</code> can be one of the existing locale categories, which permits implicit search mechanisms to find translations, but may also be another key, such as <code>[my-mod-messages]</code>. These are accessible the same as other translations, e.g. <code>{"my-mod-messages.hello"}</code>

These files are located within the language code of the language in the locale folder of the mod, so as an English example <code>__mod__/locale/en/any_name_here.cfg</code>. There can be more than 1 file per language, all of them will be read.

== Localising simple strings ==
The simplest localisation is of items, entities etc. If we say the item is <code>iron-plate</code>, the game will then search all loaded locale files for <code>item-name.iron-plate</code> and <code>item-description.iron-plate</code>, which in the locale file looks like this:

<pre>[item-name]
iron-plate=Iron plate
[item-description]
iron-plate=A plate made of iron.</pre>
If found in the locale, the label is set to this string. If not found, the game will instead show: <code>Unknown key: "item-name.iron-plate"</code>

In script, the localised string is formatted as <code>{"category.name"}</code>, so <code>game.print({"item-name.iron-plate"})</code> prints ''Iron plate''.

It is possible to use [[rich text]] features in the localised text if the location where the text is shown supports it, e.g. in the chat, prototype names and prototype tooltips.

<code>\n</code> can be used for line breaks if the location where the text is shown supports multiline text.

The list of all localization categories used by the base game is:

{| class="mw-collapsible mw-collapsed wikitable"
|-
!Localization categories
|-
|<code>[achievement-description]</code>
|-
|<code>[achievement-name]</code>
|-
|<code>[ammo-category-name]</code>
|-
|<code>[autoplace-control-names]</code>
|-
|<code>[controls]</code>
|-
|<code>[damage-type-name]</code>
|-
|<code>[decorative-name]</code>
|-
|<code>[entity-description]</code>
|-
|<code>[entity-name]</code>
|-
|<code>[equipment-name]</code>
|-
|<code>[fluid-name]</code>
|-
|<code>[fuel-category-name]</code>
|-
|<code>[item-description]</code>
|-
|<code>[item-group-name]</code>
|-
|<code>[item-limitation]</code>
|-
|<code>[item-name]</code>
|-
|<code>[map-gen-preset-description]</code>
|-
|<code>[map-gen-preset-name]</code>
|-
|<code>[mod-description]</code>
|-
|<code>[mod-name]</code>
|-
|<code>[modifier-description]
|-
|<code>[programmable-speaker-instrument]</code>
|-
|<code>[programmable-speaker-note]</code>
|-
|<code>[recipe-name]</code>
|-
|<code>[shortcut-name]</code>
|-
|<code>[story]</code>
|-
|<code>[string-mod-setting]</code>
|-
|<code>[technology-description]</code>
|-
|<code>[technology-name]</code>
|-
|<code>[tile-name]</code>
|-
|<code>[tips-and-tricks-item-description]</code>
|-
|<code>[tips-and-tricks-item-name]</code>
|-
|<code>[virtual-signal-description]</code>
|-
|<code>[virtual-signal-name]</code>
|}

== Localising with parameters ==
For more complex strings, localisation parameters can be used. For instance we want to show ''Time left: 10 minutes.''

So a key with a placeholder is defined, which is replaced by the first parameter after the locale key.:

<pre>time-left=Time left: __1__ minutes.</pre>
So it is used like this:

<syntaxhighlight lang="lua">game.print({"time-left", 10})</syntaxhighlight>
It also works with multiple parameters:

<syntaxhighlight lang="lua">game.print({"time-left", 10, 45})</syntaxhighlight>
<pre>time-left=Time left: __1__ minutes and __2__ seconds.</pre>
Which results in ''Time left: 10 minutes and 45 seconds.''

=== Built-in parameters ===
For some situations, we use localisation to show control schemes. For instance we want to say:

<pre>technology-prompt=Use T to open the technology screen</pre>
However the player may have rebound the key, but we can’t figure out which key as it would not be deterministic. So instead we use the built-in replacement functionality

<pre>technology-prompt=Use __CONTROL__open-technology-gui__ to open the technology screen.</pre>
We can also use this for items and entities:

<pre>big-iron-plate=Big __ITEM__iron-plate__</pre>
<pre>tiny-gun-turret=Tiny __ENTITY__gun-turret__</pre>

==== List of built-in parameters ====
<code>name</code> is the name of an internal game control or a prototype name, depending on context. <code>n</code> can be 1 or 2, it's used in parameters that control [[#Localising_alternate_input_names|alternate input names]]. For a list of internal game control names, see [https://lua-api.factorio.com/latest/types/LinkedGameControl.html CustomInputPrototype::linked_game_control].
* <code>__CONTROL__name__</code> - The combination of modifiers and input, such as "Control + Alt + Left-click", or "Not set".
* <code>__CONTROL_MODIFIER__name__</code> - The modifiers, such as "ControlShift", or, "No modifier selected."
* <code>__CONTROL_STYLE_BEGIN__</code>
* <code>__CONTROL_STYLE_END__</code>
* <code>__CONTROL_LEFT_CLICK__</code> is replaced with <code>control-keys.mouse-button-1</code> or <code>control-keys.controller-b</code>[https://crowdin.com/project/factorio/discussions/214]
* <code>__CONTROL_RIGHT_CLICK__</code> is replaced with <code>control-keys.mouse-button-2</code> or <code>control-keys.controller-x</code>
* <code>__CONTROL_KEY_SHIFT__</code> is replaced with <code>control-keys.shift</code> or <code>control-keys.controller-leftshoulder</code>
* <code>__CONTROL_KEY_CTRL__</code> is replaced with <code>control-keys.control</code> or <code>control-keys.controller-rightshoulder</code>
* <code>__ALT_CONTROL_LEFT_CLICK__n__</code> is replaced with <code>control-keys.mouse-button-1-alt-n</code> or <code>control-keys.controller-button-alt-n</code> (with parameter <code>control-keys.controller-b</code>)
* <code>__ALT_CONTROL_RIGHT_CLICK__n__</code> is replaced with <code>control-keys.mouse-button-2-alt-n</code> or <code>control-keys.controller-button-alt-n</code> (with parameter <code>control-keys.controller-x</code>)
* <code>__ALT_CONTROL__n__name__</code>
* <code>__CONTROL_MOVE__</code> - The Movement keys, squished together. Example: "WASD", from a conventional QWERTY English keyboard.
* <code>__REMARK_COLOR_BEGIN__</code>
* <code>__REMARK_COLOR_END__</code>
* <code>__ENTITY__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/EntityPrototype.html EntityPrototype] subclass.
* <code>__FLUID__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/FluidPrototype.html FluidPrototype].
* <code>__ITEM__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/ItemPrototype.html ItemPrototype] or subclass.
* <code>__PLANET__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/SpaceLocationPrototype.html SpaceLocationPrototype] or subclass.
* <code>__TILE__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/TilePrototype.html TilePrototype].

=== Plurals ===
Pluralization can be used in any string that uses a parameter (e.g. __1__) that is numeric, so something like an amount of minutes. It can be used multiple times per string.

<pre>format-days=__1__ __plural_for_parameter__1__{1=day|rest=days}__</pre>
This results in "1 day" and "2 days" / "500 days" etc.

The number after <code>__plural_for_parameter__</code> denotes which parameter is used to determine the plural. This is the parameter 1 in the above example. Anything inside the {} is used to make the plural. Each plural form is separated by a |.
The text in front of the = determines for what the plural form is used. Options for this are:
* A simple number, e.g. "1".
* Multiple numbers, e.g. "2,3,4".
* What the number ends with, e.g. "ends in 11" or "ends in 1"
* Multiple ends with, e.g. "ends in 1,ends in 2,ends in 12".
* "decimal" for any number with a fractional part.
* "rest" to give the default plural.

For negative numbers the plural is picked as if the number was positive, so a plural like <code>__plural_for_parameter__1__{1=day|rest=days}__</code> will result in "-1 day" for -1. 
For numbers with a SI prefix the plural is picked as if the number was fully written out, so a plural like <code>__plural_for_parameter__1__{1=day|1000=eons|rest=days}__</code> will result in "1k eons" for 1k.

Plural forms may be empty or contain other keys such as __1__ or spaces. This allows rather large plural forms:

<pre>__plural_for_parameter__1__{1=__1__ player is|rest=__1__ players are}__ connecting</pre>

The system picks the first fitting plural that it encounters when multiple would fit:
<pre>__plural_for_parameter__1__{ends in 12=option 1|ends in 2=option 2|rest=option 3}__</pre>
This will result in "option 1" for 12 and in "option 2" for 22 and in "option 3" for numbers not ending with 2.

The parameter used for pluralisation does not need to be present in the string. For example, a parameter could represent the number of list items present in another parameter:
<pre>
I like __plural_for_parameter__1__{1=only one thing:|rest=these things:} __2__
</pre>
Can result in "I like only one thing: trains", or in "I like these things: trains and turtles".

=== Concatenating localised strings ===
The special locale key: <code>""</code> is used to concatenate, as the table format does not support concatenation:

<syntaxhighlight lang="lua">game.print({"", {"item-name.iron-plate"}, ": ", 60})</syntaxhighlight>
Will result in: ''Iron plate: 60''

=== Localising alternate input names ===

In the introduction campaign, a special locale system is used for informing players how to do certain actions with their mouse.
The normal form is to use eg:
<pre>how-to-build=Use __CONTROL__build__ to place a building</pre>
which results in "Use Left mouse button to place a building". A more natural phrasing would be "Left-click to place a building", which can be achieved by using the following:
<pre>how-to-build=__ALT_CONTROL__1__build__ to place a building</pre>

These "alt" versions are controlled by a few special locale keys, mouse-button-X-alt-1 and mouse-button-X-alt-2. In English, form 1 produces eg "Left-click", and form 2 produces eg "Left-clicking". Only two alt forms ("1" and "2") are available at the moment, but if this a problem for some languages, more forms may be added in the future.
Extra mouse buttons, mouse scroll and keyboard keys are handled through the mouse-button-n-alt-1/2, mouse-wheel-alt-1/2 and keyboard-alt-1/2 keys, which just take the normal name and prepend something like "Press/Pressing", or "Scroll/Scrolling".

When translating to another language, you can use whatever forms you want here, but the important part is that you are consistent when you use the alt-forms everywhere else. It does not necessarily make sense to just copy the usages of alt forms from the English locale, and for some languages it may be more natural to simply not use this system at all.

== Accessing the localised result in code ==
While usually unneeded, it is possible to read the resulting localised text in code, for example to search in localised names.

See
[https://lua-api.factorio.com/latest/classes/LuaPlayer.html#request_translation LuaPlayer::request_translation],
[https://lua-api.factorio.com/latest/classes/LuaPlayer.html#request_translations LuaPlayer::request_translations] and
[https://lua-api.factorio.com/latest/events.html#on_string_translated on_string_translated event].

== Default Behavior(s) for finding an Unspecified Localised String ==
If a localised_string is not defined in the prototype for certain prototype classes, e.g. entity, item, Factorio may have a default search behavior.

Determining an item's localised name:
Note: the angle brackets are meant to mean a generic term, they are not part of the actual string. Also, place_result and placed_as_equipment_result are strings, and Factorio fetches the matching prototype to examine.

# if localised_name is provided in the item prototype and it is not empty {}, use the provided value
# else if there is place_result and it has localised_name that is not an empty table: {}, use the localised_name of place_result
# else if there is place_result with an empty localised_name, use {"entity-name.<entity prototype name>"}
# else if there is placed_as_equipment_result and it has a localised_name that is not an empty table: {}, use the localised_name of placed_as_equipment_result
# else if there is placed_as_equipment_result with empty localised_name, use {"equipment-name.<equipment name>"}
# else use default {"item-name.<item name>"}

Reference: [https://forums.factorio.com/viewtopic.php?p=494243#p494243]

Example: The transport-belt item does not have a localised_name, so 1->2. There is a place result, but not localised_name in the entity prototype. 2->3. The place result lacks a localised_name. Use the localised string {"entity-name.transport-belt"}

Such defaults often include a "leading key" using [<group>-name] or [<group>-description] (such as [recipe-name], [mod-setting-description]). However, each prototype may have a distinct search behavior before using those, based on presence/absence of values in the prototype. [https://lua-api.factorio.com/latest/prototypes/RecipePrototype.html RecipePrototype] for example may use the first product's localised_name, or the main_product's localised_name, or the localised string found in {"recipe-name.<recipe name>"], depending on values provided (and lacking) in the prototype.

== See also ==
* [https://lua-api.factorio.com/latest/types/LocalisedString.html LocalisedString data stage doc]
* [https://lua-api.factorio.com/latest/concepts/LocalisedString.html LocalisedString control stage doc]

[[Category:Modding]]

Tutorial:Localisation

2026-06-08T12:34:08Z

Osmo: /* Default Behavior(s) for finding an Unspecified Localised String */

{{Languages}}Mods should define human readable names for prototypes that they add. They can also define descriptions for items or custom strings for usage in GUIs etc. This is called '''localisation'''.

== File format ==
Translations are stored as .cfg files, with the following format:

<pre>welcome-message=Hello world
[category]
title=Category related title
# Comment
; Another comment</pre>
Any whitespace after or before <code>=</code> is included in the key or string, so <code>title =Category related title</code> will give an unknown key error if you are looking for the <code>title</code> key, since it is the <code>title </code> key.

<code>category</code> can be one of the existing locale categories, which permits implicit search mechanisms to find translations, but may also be another key, such as <code>[my-mod-messages]</code>. These are accessible the same as other translations, e.g. <code>{"my-mod-messages.hello"}</code>

These files are located within the language code of the language in the locale folder of the mod, so as an English example <code>__mod__/locale/en/any_name_here.cfg</code>. There can be more than 1 file per language, all of them will be read.

== Localising simple strings ==
The simplest localisation is of items, entities etc. If we say the item is <code>iron-plate</code>, the game will then search all loaded locale files for <code>item-name.iron-plate</code> and <code>item-description.iron-plate</code>, which in the locale file looks like this:

<pre>[item-name]
iron-plate=Iron plate
[item-description]
iron-plate=A plate made of iron.</pre>
If found in the locale, the label is set to this string. If not found, the game will instead show: <code>Unknown key: "item-name.iron-plate"</code>

In script, the localised string is formatted as <code>{"category.name"}</code>, so <code>game.print({"item-name.iron-plate"})</code> prints ''Iron plate''.

It is possible to use [[rich text]] features in the localised text if the location where the text is shown supports it, e.g. in the chat, prototype names and prototype tooltips.

<code>\n</code> can be used for line breaks if the location where the text is shown supports multiline text.

The list of all localization categories used by the base game is:

{| class="mw-collapsible mw-collapsed wikitable"
|-
!Localization categories
|-
|<code>[achievement-description]</code>
|-
|<code>[achievement-name]</code>
|-
|<code>[ammo-category-name]</code>
|-
|<code>[autoplace-control-names]</code>
|-
|<code>[controls]</code>
|-
|<code>[damage-type-name]</code>
|-
|<code>[decorative-name]</code>
|-
|<code>[entity-description]</code>
|-
|<code>[entity-name]</code>
|-
|<code>[equipment-name]</code>
|-
|<code>[fluid-name]</code>
|-
|<code>[fuel-category-name]</code>
|-
|<code>[item-description]</code>
|-
|<code>[item-group-name]</code>
|-
|<code>[item-limitation]</code>
|-
|<code>[item-name]</code>
|-
|<code>[map-gen-preset-description]</code>
|-
|<code>[map-gen-preset-name]</code>
|-
|<code>[mod-description]</code>
|-
|<code>[mod-name]</code>
|-
|<code>[modifier-description]
|-
|<code>[programmable-speaker-instrument]</code>
|-
|<code>[programmable-speaker-note]</code>
|-
|<code>[recipe-name]</code>
|-
|<code>[shortcut-name]</code>
|-
|<code>[story]</code>
|-
|<code>[string-mod-setting]</code>
|-
|<code>[technology-description]</code>
|-
|<code>[technology-name]</code>
|-
|<code>[tile-name]</code>
|-
|<code>[tips-and-tricks-item-description]</code>
|-
|<code>[tips-and-tricks-item-name]</code>
|-
|<code>[virtual-signal-description]</code>
|-
|<code>[virtual-signal-name]</code>
|}

== Localising with parameters ==
For more complex strings, localisation parameters can be used. For instance we want to show ''Time left: 10 minutes.''

So a key with a placeholder is defined, which is replaced by the first parameter after the locale key.:

<pre>time-left=Time left: __1__ minutes.</pre>
So it is used like this:

<syntaxhighlight lang="lua">game.print({"time-left", 10})</syntaxhighlight>
It also works with multiple parameters:

<syntaxhighlight lang="lua">game.print({"time-left", 10, 45})</syntaxhighlight>
<pre>time-left=Time left: __1__ minutes and __2__ seconds.</pre>
Which results in ''Time left: 10 minutes and 45 seconds.''

=== Built-in parameters ===
For some situations, we use localisation to show control schemes. For instance we want to say:

<pre>technology-prompt=Use T to open the technology screen</pre>
However the player may have rebound the key, but we can’t figure out which key as it would not be deterministic. So instead we use the built-in replacement functionality

<pre>technology-prompt=Use __CONTROL__open-technology-gui__ to open the technology screen.</pre>
We can also use this for items and entities:

<pre>big-iron-plate=Big __ITEM__iron-plate__</pre>
<pre>tiny-gun-turret=Tiny __ENTITY__gun-turret__</pre>

==== List of built-in parameters ====
<code>name</code> is the name of an internal game control or a prototype name, depending on context. <code>n</code> can be 1 or 2, it's used in parameters that control [[#Localising_alternate_input_names|alternate input names]]. For a list of internal game control names, see [https://lua-api.factorio.com/latest/types/LinkedGameControl.html CustomInputPrototype::linked_game_control].
* <code>__CONTROL__name__</code> - The combination of modifiers and input, such as "Control + Alt + Left-click", or "Not set".
* <code>__CONTROL_MODIFIER__name__</code> - The modifiers, such as "ControlShift", or, "No modifier selected."
* <code>__CONTROL_STYLE_BEGIN__</code>
* <code>__CONTROL_STYLE_END__</code>
* <code>__CONTROL_LEFT_CLICK__</code> is replaced with <code>control-keys.mouse-button-1</code> or <code>control-keys.controller-b</code>[https://crowdin.com/project/factorio/discussions/214]
* <code>__CONTROL_RIGHT_CLICK__</code> is replaced with <code>control-keys.mouse-button-2</code> or <code>control-keys.controller-x</code>
* <code>__CONTROL_KEY_SHIFT__</code> is replaced with <code>control-keys.shift</code> or <code>control-keys.controller-leftshoulder</code>
* <code>__CONTROL_KEY_CTRL__</code> is replaced with <code>control-keys.control</code> or <code>control-keys.controller-rightshoulder</code>
* <code>__ALT_CONTROL_LEFT_CLICK__n__</code> is replaced with <code>control-keys.mouse-button-1-alt-n</code> or <code>control-keys.controller-button-alt-n</code> (with parameter <code>control-keys.controller-b</code>)
* <code>__ALT_CONTROL_RIGHT_CLICK__n__</code> is replaced with <code>control-keys.mouse-button-2-alt-n</code> or <code>control-keys.controller-button-alt-n</code> (with parameter <code>control-keys.controller-x</code>)
* <code>__ALT_CONTROL__n__name__</code>
* <code>__CONTROL_MOVE__</code> - The Movement keys, squished together. Example: "WASD", from a conventional QWERTY English keyboard.
* <code>__REMARK_COLOR_BEGIN__</code>
* <code>__REMARK_COLOR_END__</code>
* <code>__ENTITY__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/EntityPrototype.html EntityPrototype] subclass.
* <code>__FLUID__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/FluidPrototype.html FluidPrototype].
* <code>__ITEM__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/ItemPrototype.html ItemPrototype] or subclass.
* <code>__PLANET__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/SpaceLocationPrototype.html SpaceLocationPrototype] or subclass.
* <code>__TILE__name__</code> - The localised name of the [https://lua-api.factorio.com/latest/prototypes/TilePrototype.html TilePrototype].

=== Plurals ===
Pluralization can be used in any string that uses a parameter (e.g. __1__) that is numeric, so something like an amount of minutes. It can be used multiple times per string.

<pre>format-days=__1__ __plural_for_parameter__1__{1=day|rest=days}__</pre>
This results in "1 day" and "2 days" / "500 days" etc.

The number after <code>__plural_for_parameter__</code> denotes which parameter is used to determine the plural. This is the parameter 1 in the above example. Anything inside the {} is used to make the plural. Each plural form is separated by a |.
The text in front of the = determines for what the plural form is used. Options for this are:
* A simple number, e.g. "1".
* Multiple numbers, e.g. "2,3,4".
* What the number ends with, e.g. "ends in 11" or "ends in 1"
* Multiple ends with, e.g. "ends in 1,ends in 2,ends in 12".
* "decimal" for any number with a fractional part.
* "rest" to give the default plural.

For negative numbers the plural is picked as if the number was positive, so a plural like <code>__plural_for_parameter__1__{1=day|rest=days}__</code> will result in "-1 day" for -1. 
For numbers with a SI prefix the plural is picked as if the number was fully written out, so a plural like <code>__plural_for_parameter__1__{1=day|1000=eons|rest=days}__</code> will result in "1k eons" for 1k.

Plural forms may be empty or contain other keys such as __1__ or spaces. This allows rather large plural forms:

<pre>__plural_for_parameter__1__{1=__1__ player is|rest=__1__ players are}__ connecting</pre>

The system picks the first fitting plural that it encounters when multiple would fit:
<pre>__plural_for_parameter__1__{ends in 12=option 1|ends in 2=option 2|rest=option 3}__</pre>
This will result in "option 1" for 12 and in "option 2" for 22 and in "option 3" for numbers not ending with 2.

The parameter used for pluralisation does not need to be present in the string. For example, a parameter could represent the number of list items present in another parameter:
<pre>
I like __plural_for_parameter__1__{1=only one thing:|rest=these things:} __2__
</pre>
Can result in "I like only one thing: trains", or in "I like these things: trains and turtles".

=== Concatenating localised strings ===
The special locale key: <code>""</code> is used to concatenate, as the table format does not support concatenation:

<syntaxhighlight lang="lua">game.print({"", {"item-name.iron-plate"}, ": ", 60})</syntaxhighlight>
Will result in: ''Iron plate: 60''

=== Localising alternate input names ===

In the introduction campaign, a special locale system is used for informing players how to do certain actions with their mouse.
The normal form is to use eg:
<pre>how-to-build=Use __CONTROL__build__ to place a building</pre>
which results in "Use Left mouse button to place a building". A more natural phrasing would be "Left-click to place a building", which can be achieved by using the following:
<pre>how-to-build=__ALT_CONTROL__1__build__ to place a building</pre>

These "alt" versions are controlled by a few special locale keys, mouse-button-X-alt-1 and mouse-button-X-alt-2. In English, form 1 produces eg "Left-click", and form 2 produces eg "Left-clicking". Only two alt forms ("1" and "2") are available at the moment, but if this a problem for some languages, more forms may be added in the future.
Extra mouse buttons, mouse scroll and keyboard keys are handled through the mouse-button-n-alt-1/2, mouse-wheel-alt-1/2 and keyboard-alt-1/2 keys, which just take the normal name and prepend something like "Press/Pressing", or "Scroll/Scrolling".

When translating to another language, you can use whatever forms you want here, but the important part is that you are consistent when you use the alt-forms everywhere else. It does not necessarily make sense to just copy the usages of alt forms from the English locale, and for some languages it may be more natural to simply not use this system at all.

== Accessing the localised result in code ==
While usually unneeded, it is possible to read the resulting localised text in code, for example to search in localised names.

See
[https://lua-api.factorio.com/latest/classes/LuaPlayer.html#request_translation LuaPlayer::request_translation],
[https://lua-api.factorio.com/latest/classes/LuaPlayer.html#request_translations LuaPlayer::request_translations] and
[https://lua-api.factorio.com/latest/events.html#on_string_translated on_string_translated event].

== Default Behavior(s) for finding an Unspecified Localised String ==
If a localised_name or localised_description is not defined in the prototype or is an empty table: {}, Factorio may have a default search behavior.

For most types, the name defaults to {"<base type>-name.<prototype name>"}, for example {"entity-name.underground-belt"}

Similarly, the description defaults to {"<base type>-description.<prototype name>"}, for example {"entity-description.underground-belt"}

Note: the angle brackets are meant to mean a generic term, they are not part of the actual string.

For items, the process is more complicated:
# if localised_name is provided in the item prototype and it is not empty {}, use the provided value
# else if the item prototype has a place_result:
#:# if place_result has localised_name that is not an empty table: {}, use the localised_name of place_result
#:# else if {"entity-name.<place_result name>"} has a translation, use it
#:# else use {"item-name.<item name>"}
# else if the item prototype has a placed_as_equipment_result:
#:# if place_result has a localised_name that is not an empty table: {}, use the localised_name of placed_as_equipment_result
#:# else if {"equipment-name.<place_as_equipment_result name>"} has a translation, use it
#:# else use {"item-name.<item name>"}
# else if the item prototype has a placed_as_tile:
#:# if place_as_tile result has a localised_name that is not an empty table: {}, use the localised_name of placed_as_tile result
#:# else if {"tile-name.<place_as_tile result name>"} has a translation, use it
#:# else use {"item-name.<item name>"}
# else use {"item-name.<item name>"}
Descriptions of items are found in the same way, except localised_description is used instead of localised_name and <base type>-description is used instead of <base type>-name.

Reference: [https://forums.factorio.com/viewtopic.php?p=494243#p494243] 

Example: The transport-belt item does not have a localised_name, so 1->2. There is a place result, but not localised_name in the entity prototype. 2->3. The place result lacks a localised_name. Use the localised string {"entity-name.transport-belt"}

Such defaults often include a "leading key" using [<group>-name] or [<group>-description] (such as [recipe-name], [mod-setting-description]). However, each prototype may have a distinct search behavior before using those, based on presence/absence of values in the prototype. [https://lua-api.factorio.com/latest/prototypes/RecipePrototype.html RecipePrototype] for example may use the first product's localised_name, or the main_product's localised_name, or the localised string found in {"recipe-name.<recipe name>"], depending on values provided (and lacking) in the prototype.

== See also ==
* [https://lua-api.factorio.com/latest/types/LocalisedString.html LocalisedString data stage doc]
* [https://lua-api.factorio.com/latest/concepts/LocalisedString.html LocalisedString control stage doc]

[[Category:Modding]]

Command line parameters

2026-04-24T03:41:35Z

Osmo: Add --enable-lua-udp

{{Languages}}__TOC__

Command line parameters can be used to set settings in the command line before the game launches, this is useful mainly for advanced users or server hosts.

{| class="wikitable"
|+General options
|-
| -h, --help
|
| display help
|-
| --version
|
| show version information
|-
| -v, --verbose
|
| enable verbose logging
|-
| -c, --config
| PATH
| config file to use
|-
| --no-log-rotation
|
| don't rotate log file
|-
| --mod-directory
| PATH
| Mod directory to use
|-
| --check-unused-prototype-data
|
| Print a warning for all prototype values that were not accessed. Note for mod authors: If an entry is unused and is a table that contains the key/value pair 'ignore' with the value 'true' then the entire entry is ignored.
|-
| --executable-path
| PATH
| Override autodetected __PATH__executable. Usually not needed except on very weird systems.
|}

{| class="wikitable"
|+ Running options
|-
| -s, --map2scenario
| arg
| map to scenario conversion
|-
| -m, --scenario2map
| arg
| scenario to map conversion
|-
| --apply-update
| arg
| immediately apply update package
|-
| --create
| FILE
| create a new map
|-
| --map-gen-settings
| FILE
| Map generation settings for use with <code>--create</code>, <code>--start-server-load-scenario</code> or <code>--generate-map-preview</code>. See data/map-gen-settings.example.json
|-
| --map-gen-seed
| SEED
| Map generation seed for use with --create, --start-server-load-scenario or --generate-map-preview. Will override seed specified in map gen settings
|-
| --map-gen-seed-max
| SEED
| Map generation seed for use with --generate-map-preview to generate multiple previews using every second seed in the interval from map-gen-seed to map-gen-seed-max.
|-
| --map-settings
| FILE
| Map settings for use with --create or --start-server-load-scenario. See data/base/prototypes/map-settings.lua
|-
| --preset
| arg
| Name of the map generation preset to be used.
|-
| --generate-map-preview
| PATH
| Generate preview images of the map; PATH should name a PNG file or end with a '/' or '\' to indicate a directory.
|-
| --generate-map-preview-random
| COUNT
| Number of maps to generate with a random seed using --generate-map-preview.
|-
| --map-preview-size
| SIZE
| Size (in pixels) of map preview (default: 1024)
|-
| --map-preview-offset
| X,Y
| Offset of the center of the map, in meters (default: 0,0)
|-
| --map-preview-planet
| PLANET
| Planet to generate the preview for (default: nauvis)
|-
| --report-quantities
| PROTOTYPE,...
| When generating map preview, report approximate quantities of the named entity prototypes
|-
| --threads
| THREADCOUNT
| Number of threads to use when generating map previews
|-
| --disable-migration-window
|
| Disables the gui that is shown when opening a save with migrated content
|-
| --instrument-mod
| arg
| Name of a mod to enable [https://lua-api.factorio.com/latest/auxiliary/instrument.html Instrument Mode]
|-
| --sync-mods
| FILE
| Sync mods with save. Note for headless servers: requires <code>service-username</code> and <code>service-token</code> to be set in the player-data.json file if any mods need to be downloaded.
|-
| --enable-unsafe-lua-debug-api
|
| Enables unsafe functions in the Lua debug library.
|-
| --enable-lua-udp
| arg
| Set local port and enable [https://lua-api.factorio.com/latest/classes/LuaHelpers.html#send_udp helpers.send_udp()] and and [https://lua-api.factorio.com/latest/classes/LuaHelpers.html#recv_udp helpers.recv_udp()]
|-
| --host
| FILE
| Start hosting a multiplayer game
|-
| --host-interactive
| FILE
| Open multiplayer server settings for hosting the selecting save
|-
| --start-server
| FILE
| start a multiplayer server
|-
| --start-server-load-scenario
| [MOD/]NAME
| start a multiplayer server and load the specified scenario. The scenario is looked for inside the given mod. If no mod is given, it is looked for in the top-level scenarios directory.
|-
| --start-server-load-latest
|
| start a multiplayer server and load the latest available save
|-
| --until-tick
| TICK
| run a save until given map tick
|-
| --benchmark
| FILE
| load save and run benchmark
|-
| --benchmark-ticks
| N
| number of ticks for benchmarking. Default is 1000
|-
| --benchmark-runs
| N
| how often the number of ticks will be run, map will reload after each run. Default is 1
|-
| --benchmark-verbose
| timings
| comma separated list of Update timings to output each tick. "all", "timestamp" as well as all other values seen in the debug show-time-usage view's Update section are allowed here. An empty string disabled verbose benchmarking. Timings are returned in nanoseconds.
|-
| --benchmark-sanitize
|
| only output the final benchmark results
|-
| --benchmark-ignore-paused
|
| leaves the game paused if it was paused when saved. By default the game is unpaused when a benchmark starts.
|-
| --output-perf-stats
| FILE
| path of file to which rendering performance statistics measurements should be saved. Special tags {api}, {hw}, {time} and {tag} will be replaced.
|-
| --dump-data
|
| dumps data.raw as JSON to the script output folder and exits.
|-
| --dump-icon-sprites
|
| dumps all icon sprites as png files to the script output folder and exits.
|-
| --dump-prototype-locale
|
| dumps all prototypes name and description (if they have a valid value) to the script output folder and exits.
|-
| --report-autogenerated-icon-mipmaps
|
| Report which icons will have generated mipmaps.
|-
| --log-shared-tile-layers
|
| After loading prototypes logs which tile layers are shared by multiple prototypes and lists the prototypes that share them.
|-
| --log-spritesheets-to-optimize
| N
| Logs N spritesheets that seem to have some nearly transparent noise, and could be made much smaller if the noise was cleaned up.
|-
| --mp-connect
| ADDRESS
| start factorio and connect to address
|-
| --password
| PASSWORD
| the password to use when using mp-connect (if any)
|-
| --heavy
|
| run the game in heavy mode if singleplayer with graphics. (heavy mode is related to investigating desyncs, see [[Desynchronization#Using_heavy_mode_command]])
|-
| --load-game
| FILE
| start Factorio and load a game in singleplayer
|-
| --load-scenario
| [MOD/]NAME
| start Factorio and load the specified scenario in singleplayer. The scenario is looked for inside the given mod. If no mod is given, it is looked for in the top-level scenarios directory.
|-
| --benchmark-graphics
| FILE
| load save and run it with graphics for benchmark-ticks number of ticks as normal game would
|-
| --benchmark-frame
| FILE
| load save and benchmark graphics rendering of single frame (prepare + render) without updating the game
|-
| --force-opengl
|
|use OpenGL for rendering (windows, mac only)
|-
| --force-d3d
|
|use Direct3D for rendering (windows only)
|-
| --d3d-adapter
| ID
|adapter which should be used to initialized Direct3D (windows only)
|-
| --d3d-feature-level
|
|override feature level (11, 10.1, 10) (windows only)
|-
| --dxgi-blit-model
|
|force Blit presentation mode (windows only)
|-
| --force-metal
|
|use Metal for rendering (mac only)
|-
| --debug-graphics
|
| enables debugging layer for graphics API. If DirectX is used DirectX SDK needs to be installed for this to work.
|-
| --fullscreen
| BOOL
| start game in windowed mode (saved to configuration)
|-
| --max-texture-size
| N
| maximal size of texture that the game can use (saved to configuration). Should be power of two greater than 2048
|-
| --graphics-quality
| arg
| accepted values: high, medium
|-
| --video-memory-usage
| arg
| accepted values: all, high, medium, low
|-
| --force-graphics-preset
| arg
| accepted values: very-low, low, mac-with-low-ram, medium-with-low-vram, medium, high, very-high, extreme
|-
| --gfx-safe-mode
|
| resets some graphics settings to values that should work on most configurations
|-
| --low-vram
|
| sprites that are not put into sprite atlases won't be allocated as texture objects
|-
| --shader
| arg
| enable/disable shader postprocessing (saved to configuration)
|-
| --disable-audio
|
| Disable audio. Mainly for faster startup during development.
|-
| --window-size
| arg
| Desired window resolution. For example "1680x1050". Or "maximized"
|-
| --single-thread-loading
|
| Disables loading of sprites in multiple threads.
|-
| --cache-sprite-atlas
| BOOL
| Enable/disable sprite atlas cache.
|-
| --nogamepad
|
| Disable gamepad(controller) support
|}

{| class="wikitable"
|+ Server options
|-
| --port
| N
| network port to use
|-
| --bind
| ADDRESS[:PORT]
| IP address (and optionally port) to bind to
|-
| --rcon-port
| N
| Port to use for RCON
|-
| --rcon-bind
| ADDRESS:PORT
| IP address and port to use for RCON
|-
| --rcon-password
| PASSWORD
| Password for RCON
|-
| --server-settings
| FILE
| Path to file with server settings. See data/server-settings.example.json
|-
| --use-server-whitelist
| BOOL
| If the whitelist should be used.
|-
| --use-authserver-bans
|
| Verify that connecting players are not banned from multiplayer and inform Factorio.com about ban/unban commands.
|-
| --server-whitelist
| FILE
| Path to file with server whitelist.
|-
| --server-banlist
| FILE
| Path to file with server banlist.
|-
| --server-adminlist
| FILE
| Path to file with server adminlist.
|-
| --console-log
| FILE
| Path to file where a copy of the server's log will be stored
|-
| --server-id
| FILE
| Path where server ID will be stored or read from
|}

=== Boolean options ===

Parameters shown above with a BOOL option must be formatted as <code>[parameter]=true</code> or <code>[parameter]=false</code>. For example,

--fullscreen=false

will start the game in windowed (not fullscreen) mode.

=== Multiplayer ===

--start-server SAVE

Will start a Headless (Dedicated) server, with no GUI.

--mp-connect ADDRESS
ADDRESS is the IP:port of the remote host. Port is optional.
Examples:

./factorio --mp-connect 192.168.1.101
./factorio --mp-connect 192.168.1.101:2345

As above, port can be specified by placing the port number after a colon in the address.

=== Creating a map from custom settings ===

Sometimes it's useful to create a new game with map and/or map generator settings stored in a JSON file rather than going through the in-game map settings screen.
One reason is that by editing the settings directly it is possible to set settings outside the range normally available from the GUI.

To do this, Factorio is run from the command-line, and a JSON file containing the map generator settings and a JSON file containing map settings (if customizing them) are needed.

Example for custom generator settings:
<pre>{
"terrain_segmentation": 0.5,
"water": "2",
"width": 0,
"height": 0,
"starting_area": "normal",
"peaceful_mode": false,
"autoplace_controls":
{
"coal": {"frequency": 1, "size": 2, "richness": 0.5},
"copper-ore": {"frequency": "low", "size": "normal", "richness": "high"},
"crude-oil": {"frequency": "normal", "size": "normal", "richness": "normal"},
"enemy-base": {"frequency": "normal", "size": "normal", "richness": "normal"},
"iron-ore": {"frequency": "normal", "size": "normal", "richness": "normal"},
"stone": {"frequency": "normal", "size": 0, "richness": "normal"},
"uranium-ore": {"frequency": "normal", "size": "none", "richness": "normal"}
},

"cliff_settings":
{
"name": "cliff",
"cliff_elevation_0": 30,
"cliff_elevation_interval": 20,
"richness": 1
},

"property_expression_names":
{
"elevation": "0_16-elevation",
"temperature": "35"
},

"seed": null
}
</pre>

Note that this is the same format as [https://lua-api.factorio.com/latest/concepts/MapGenSettings.html MapGenSettings] that are modifiable from Lua. Everything in the file is optional.

Creating a custom save:
<pre>
"C:\Program Files\Factorio\bin\x64\Factorio.exe" --create stuff-seed123.zip --map-gen-settings map-gen-settings.json --map-gen-seed 123
</pre>

Generating a map preview:
<pre>
"C:\Program Files\Factorio\bin\x64\Factorio.exe" --generate-map-preview preview-seed123.png --map-gen-settings map-gen-settings.json --map-gen-seed 123
</pre>

==== Creating the JSON files from a map exchange string ====

It can be useful to create the initial JSON files from a known map exchange string instead of creating them from scratch. To convert the map exchange string to JSON, open the game and run the following command with your map exchange string:

/c helpers.write_file('map.txt', helpers.table_to_json(helpers.parse_map_exchange_string("<your exchange string here>")))

Then open the script_output folder in the [[user data directory]] and open map.txt - it will look like this:

{"map_settings":{ ...<MAP_SETTINGS> ... },"map_gen_settings":{ ...<MAP_GEN_SETTINGS>... }}

Copy the { ...<MAP_SETTINGS> ... } section into a new file called 'map-settings.json' in the desired location. Copy the { ...<MAP_GEN_SETTINGS> ... } section section into a new file called 'map-gen-settings.json' in the desired location.

== See also ==
* [[Console]]

{{C|Modding}}

Settings

2026-01-06T06:49:56Z

Osmo: typo

{{Languages}}
{{Stub}}

Factorio has a number of '''settings''' in different places, this page covers the ones accessible through the Main menu and Game (pause) menu. These settings are also saved to and can be changed from the "config.ini" file in the Factorio [[Application_directory#User_data_directory|user data directory]]. The [[#See also]] section covers other places that allow configuring the game.

== Controls ==

See [[Controls]]

== Mod settings ==

Settings added by mods are placed here. There are 3 sections: Startup, Map and Per player. Each section contains a list of settings, grouped per mod that added them.

Startup settings require the game to be restarted. This means closing and opening the game, not resetting progress in a save file. Map settings can be changed while the game is running. Per player settings can be changed while the game is running and allow each player to have different values in the settings.

See also: [[Tutorial:Mod settings]]

== Hidden settings ==

Factorio supports a number of hidden configuration options that are not normally shown in the GUI. They can be accessed by holding CTRL + ALT when clicking the "Settings" button in the pause menu, which will cause a new button labeled "The rest" to appear.

These settings may be experimental and may not be validated for safety, so change them at your own risk.

{| class="wikitable"
|+ Notable hidden settings
|-
! Name !! Default !! Description
|-
| autosave-slots || 3 || How many autosaves to keep on a rolling basis
|-
| non-blocking-saving || false || Only works on Mac and Linux. When set to true, saves do not cause the game to pause. [https://forums.factorio.com/viewtopic.php?t=57464]
|-
| technology-gui-pauses-game || true || By setting to false, the game will no longer pause in single player when opening the technology tree.
|-
| cache-prototype-data || false || When enabled, significantly speeds up the "Building prototypes..." step when starting the game at the cost of increased storage space, if prototypes haven't changed since last startup. The cache needs to be built first, so the loading time will increase when rebuilding it, such as when the setting is enabled for the first time.
|-
| cache-sprite-atlas || false || When enabled, significantly speeds up the "Loading sprites..." step when starting the game at the cost of increased storage space, if sprites haven't changed since last startup. The cache needs to be built first, so the loading time will increase when rebuilding it, such as when the setting is enabled for the first time.
|-
| main-menu-simulation-selector || false || Shows a dropdown on the main menu allowing to select a simulation to play in the background. Can be useful for modders when creating custom simulations.
|}

== See also ==

* [[Debug mode|Debug options]]
* [[Command line parameters]]
* [[Map generator]]

Settings

2025-10-23T04:32:45Z

Osmo: Links to multiple relevant pages, added more information, covered settings other than hidden settings.

{{Stub}}

Factorio has a number of '''settings''' in different places, this page covers the ones accessible through the Main menu and Game (pause) menu. These settings are also saved to and can be changed from the "config.ini" file in the Factorio [[Application_directory#User_data_directory|user data directory]]. The [[#See also]] section covers other places that allow configuring the game.

== Controls ==

See [[Controls]]

== Mod settings ==

Settings added by mods are placed here. There are 3 sections: Startup, Map and Per player. Each section contains a list of settings, grouped per mod that added them.

Startup settings require the game to be restarted. This means closing and opening the game, not resetting progress in a save file. Map settings can be changed while the game is running. Per player settings can be changed while the game is running and allow each player to have different values in the settings.

See also: [[Tutorial:Mod settings]]

== Hidden settings ==

Factorio supports a number of hidden configuration options that are not normally shown in the GUI. They can be accessed by holding CTRL + ALT when clicking the "Settings" button in the pause menu, which will cause a new button labeled "The rest" to appear.

These settings may be experimental and may not be validated for safety, so change them at your own risk.

{| class="wikitable"
|+ Notable hidden settings
|-
! Name !! Default !! Description
|-
| autosave-slots || 3 || How many autosaves to keep on a rolling basis
|-
| non-blocking-saving || false || Only works on Mac and Linux. When set to true, saves do not cause to game to pause. [https://forums.factorio.com/viewtopic.php?t=57464]
|-
| technology-gui-pauses-game || true || By setting to false, the game will no longer pause in single player when opening the technology tree.
|-
| cache-prototype-data || false || When enabled, significantly speeds up the "Building prototypes..." step when starting the game at the cost of increased storage space, if prototypes haven't changed since last startup. The cache needs to be built first, so the loading time will increase when rebuilding it, such as when the setting is enabled for the first time.
|-
| cache-sprite-atlas || false || When enabled, significantly speeds up the "Loading sprites..." step when starting the game at the cost of increased storage space, if sprites haven't changed since last startup. The cache needs to be built first, so the loading time will increase when rebuilding it, such as when the setting is enabled for the first time.
|-
| main-menu-simulation-selector || false || Shows a dropdown on the main menu allowing to select a simulation to play in the background. Can be useful for modders when creating custom simulations.
|}

== See also ==

* [[Debug mode|Debug options]]
* [[Command line parameters]]
* [[Map generator]]

Rich text

2025-09-15T22:33:10Z

Osmo: Fix syntactical error

{{Languages}}
Rich text formatting allows the use of tags within most of the game's textboxes to change the visual formatting of text or to embed interactable images/entities. Predefined text tags are employed for this purpose.

== Tags ==

Tags are useful for sharing blueprints, marking map locations in chat or adding icons to map markers and train stations.
Ctrl+alt clicking the map or ground will automatically insert a gps tag and post it into [[console|chat]].

Shift clicking most things with the console open will insert a tag for that thing into chat. The chat and many other textboxes in the game have a button on the right edge that opens an icon selector. This can be used to easily insert rich text tags of recipes, items, fluids, virtual signals and entities into the textbox.

When used in chat, the tag image will be followed by a text description, except for the img tag.
Used elsewhere only the image is shown.

{| class="wikitable"
|-
! style="width:20%"| Syntax
! style="width:15%"| Example Input
! style="width:15%"| Example Result
! style="width:50%"| Description

|-
| [img=class/name] 
[img=class.name] 
[img=sprite-prototype-name]
| [img=item.iron-plate] 
[img=quantity-time] 
[img=utility/played_green]
| [[File:Iron_plate.png|28px]] 
[[File:Time_icon.png|28px]] 
[[File:Played green.png|28px]]
| Embeds only a small inline game graphic. The period format must be used in game save names. This tag uses [https://lua-api.factorio.com/latest/concepts/SpritePath.html sprite paths]:
class is any of: item, entity, technology, recipe, item-group, fluid, tile, virtual-signal, achievement, equipment, space-location or utility.

name: see below

sprite-prototype-name is the [[Data.raw#sprite|internal-name]] of a [[Prototype/Sprite|sprite prototype]].

|-
| [item=name]
| [item=iron-plate]
| [[File:Iron_plate.png|28px]] [Item: Iron plate]
| name is the internal-name of the item

|-
| [entity=name]
| [entity=small-biter]
| [[File:Small_biter.png|28px]] [Entity: Small biter]
| name is the internal-name of the entity

|-
| [technology=name]
| [technology=logistics]
| [[File:Logistics_(research).png|28px]] [Technology: Logistics]
| name is the internal-name of the technology

|-
| [recipe=name]
| [recipe=basic-oil-processing]
| [[File:Basic_oil_processing.png|28px]] [Recipe: Basic oil processing]
| name is the internal-name of the recipe, usually the item name

|-
| [item-group=name]
| [item-group=combat]
| [[File:Item-group_military.png|28px]] [Item Group: Combat]
| name is any of: logistics, production, intermediate-products, combat, fluids or signals

|-
| [fluid=name]
| [fluid=water]
| [[File:Water.png|28px]] [Fluid: Water]
| name is the internal name of the fluid

|-
| [tile=name]
| [tile=grass-3]
| [[File:Grass_3.png|28px]] [Tile: Grass 3]
| name is the internal name of the tile, usually the lowercase name with hyphens replacing spaces as written from the map editor

|-
| [virtual-signal=name]
| [virtual-signal=signal-A]
| [[File:Signal-A.png|28px]] [Virtual Signal: Signal A]
| name is the word signal followed by either an uppercase letter, number, color, each, everything or anything

|-
| [achievement=name]
| [achievement=minions]
| [[File:Minions-achievement.png|28px]] [Achievement: Minions]
| name is the internal-name of the achievement, usually the lowercase name with hyphens replacing spaces

|-
| [gps=x,y]
[gps=x,y,surface]
| [gps=0,0]
| [[File:Map.png|28px]] [Location: 0,0]
| Embeds a map location and marks the location on the map of other players.
x is the x point coordinate 
y is the y point coordinate 
surface is the current surface. Is only added if the player Ctrl+alt clicks on a surface that is not the default surface. When the player is on another surface than surface, clicking the tag does nothing. Mods must handle this case with [https://lua-api.factorio.com/latest/events.html#on_player_clicked_gps_tag on_player_clicked_gps_tag]
|-
| [special-item=blueprint_string]
|
| [[File:Blueprint.png|28px]] [Blueprint]
| Embeds a blueprint. Players can get a blueprint item by clicking the icon.
blueprint_string is the blueprint string of a blueprint, deconstruction planner or upgrade planners

|-
| [armor=player]
| [armor=Player]
| [[File:Power_armor_MK2.png|28px]] [Armor: Player]
| Embeds the armor of a player. Allows other players to see the equipment installed.
player is the name of the player

|-
| [train=number]
| [train=93]
| [[File:Locomotive.png|28px]] [Train: 2]
| Embeds a reference to a train. Clicking the icon will open the train GUI for that train.
number is the internal unit number of the train

|-
| [train-stop=number]
| [train-stop=100]
| [[File:Train_stop.png|28px]] [Train Stop: Trangar]
| Embeds a reference to a train stop. Clicking the icon will open the GUI for that train stop.
number is the internal unit number of the train stop

|-
| [shortcut=shortcut-name]
| [shortcut=give-spidertron-remote]
| [[File:Spidertron_remote.png|28px]] [Shortcut: Create spidertron remote]
| Embeds a reference to a shortcut from the [[Shortcut bar]]. Hovering over the rich text will show the shortcut's description. Clicking the rich text will act as if you clicked the shortcut.
shortcut-name is the internal name of the shortcut.

|-
| [tip=tip-name]
| [tip=spidertron-control]
| [[File:Tip.png|28px]] [Tip: Spidertron control]
| Embeds a reference to a tip from the "Tips and tricks" menu. Hovering over the icon will show the tip's text. Clicking the icon will open the "Tips and tricks" menu to that page.

|-
| [tooltip=text,tooltip locale key]
| [tooltip=Hover to see "Iron plate",item-name.iron-plate]
| [[File:Custom-tag-icon.png|28px]] Hover to see "Iron plate"
| Shows the given text with a tooltip that is specified with a [[Tutorial:Localisation#Localising_simple_strings|locale key]].

|-
| [quality=tier] 
[item=name,quality=tier] 
[entity=name,quality=tier] 

|[quality=normal] 
[item=iron-plate,quality=normal] 
[entity=small-biter,quality=uncommon] 

| [[File:Quality normal.png|28px]] [Quality: Normal] 
[[File:Iron_plate.png|28px]] [Item: Iron plate] 
[[File:Uncommon small biter.png|28px]] [Entity: Uncommon Small biter] 
|
[[Quality]] can also be optionally specified on the following tags: item, entity, recipe, fluid, and virtual-signal 
It can also be added to the other tags that use name, but they ignore it.

The normal quality is the default quality and won't modify tags. Any other quality won't exist without [[Space Age]] and Quality

tier is the internal-name of the quality

|-
| [space-platform=number]
| [space-platform=3]
| [[File:Space_platform_hub.png|28px]] [Space platform: My cool space platform]
| number is the internal id of a space-platform, starting with 1.
Hovering over the rich text will show a view of the space platform. Clicking the rich text will go to the platform in remote view.

|-
| [planet=name]
| [planet=gleba]
| [[File:Gleba.png|28px]] [Planet: Gleba]
| name is the internal name of a planet.
Available planets in Space Age are: nauvis, gleba, fulgora, vulcanus, and aquilo.

[[Nauvis]] is part of the base game and will always be available.

|-
| [space-location=name]
| [space-location=shattered-planet]
[space-location=gleba]
| [[File:Shattered planet.png|28px]] [Space location: Shattered Planet]
[[File:Gleba.png|28px]] [Planet: Gleba]
| name is the internal name of a space-location in Space Age.
Available locations in Space Age are: nauvis, gleba, fulgora, vulcanus, aquilo, solar-system-edge, and shattered-planet.

For the planet's listed in the section above 'planet' will be used as the text prefix instead of 'space-location'

|-
| [space-age]
| [space-age]
| [[File:Space_age_icon.png|28px]]
| Embeds the Space Age icon.
|}

== Text modifiers ==
[[File:Fonts.png|right|thumbnail|100px|Different fonts displayed in-game. (Click to enlarge.)]]

The color and font of text can be changed

{| class="wikitable"
|-
! style="width:20%"| Syntax
! style="width:15%"| Example Input
! style="width:15%"| Example Result
! style="width:50%"| Description
|-
| [color=rgb]...[/color] 
[color=#rrggbb]...[/color] 
[color=#aarrggbb]...[/color] 
[color=rgb]...[.color] 
[color=#rrggbb]...[.color] 
[color=#aarrggbb]...[.color]
| [color=red]Red[/color] text 
[color=1,0,0]Red[/color] text 
[color=255,0,0]Red[/color] text 
[color=#ff0000]Red[/color] text
| Red text
| rgb is a comma separated RGB color ranging from 0 to 1 or 0 to 255, or a color name
Available colors: default, red, green, blue, orange, yellow, pink, purple, white, black, gray, brown, cyan, acid.
|-
| [font=font-name]...[/font] 
[font=font-name]...[.font]
| [font=default-bold]Bold text[/font]
| Bold text
| font-name is the name of the [[Data.raw#font|Factorio font]] to render
|}

== See also ==
* [[Console]]
* [[Data.raw]] for the list of internal names of recipes, technologies, fluids, etc.

{{C|GUI}}