Translations

Theme localization guide.


The built-in themes that are included with MkDocs provide support for translations. This is a guide for translators, which documents the process for contributing new translations and/or updating existing translations. For guidance on modifying the existing themes, see the Contributing Guide. To enable a specific translation see the documentation about the specific theme you are using in the User Guide. For translations of third-party themes, please see the documentation for those themes. For a third-party theme to make use of MkDocs' translation tools and methods, that theme must be properly configured to make use of those tools.

Note

Translations only apply to text contained within a theme's template, such as "next" and "previous" links. The Markdown content of a page is not translated. If you wish to create multilingual documentation, you need to combine theme localization with a third-party internationalization/localization plugin.

Localization tooling prerequisites

Theme localization makes use of the babel project for generation and compilation of localization files. You will need to be working from the git working tree on your local machine to make use of the translation commands.

See the Contributing Guide for direction on how to Install for Development and Submit a Pull Request. The instructions in this document assume that you are working from a properly configured development environment.

Make sure translation requirements are installed in your environment:

pip install 'mkdocs[i18n]'

Adding language translations to themes

If your favorite language locale is not yet supported on one (or both) of the built-in themes (mkdocs and readthedocs), you can easily contribute a translation by following the steps below.

Here is a quick summary of what you'll need to do:

  1. Fork and clone the MkDocs repository and then install MkDocs for development for adding and testing translations.
  2. Initialize new localization catalogs for your language (if a translation for your locale already exists, follow the instructions for updating theme localization files instead).
  3. Add a translation for every text placeholder in the localized catalogs.
  4. Locally serve and test the translated themes for your language.
  5. Update the documentation about supported translations for each translated theme.
  6. Contribute your translation through a Pull Request.

Note

Translation locales are usually identified using the ISO-639-1 (2-letter) language codes. While territory/region/county codes are also supported, location specific translations should only be added after the general language translation has been completed and the regional dialect requires use of a term which differs from the general language translation.

Fork and clone the MkDocs repository

In the following steps you'll work with a fork of the MkDocs repository. Follow the instructions for forking and cloning the MkDocs repository.

To test the translations you also need to install MkDocs for development from your fork.

Initializing the localization catalogs

The templates for each theme contain text placeholders that have been extracted into a Portable Object Template (messages.pot) file, which is present in each theme's folder.

Initializing a catalog consists of running a command which will create a directory structure for your desired language and prepare a Portable Object (messages.po) file derived from the pot file of the theme.

Use the init_catalog command on each theme's directory and provide the appropriate language code (-l <language>).

The language code is almost always just two lowercase letters, such as sv, but in some cases it needs to be further disambiguated.

See:

In particular, the way to know that the pt language should be disambiguated as pt_PT and pt_BR is that the Language subtag registry page contains pt- if you search for it. Whereas sv should remain just sv, because that page does not contain sv-.

So, if we pick es (Spanish) as our example language code, to add a translation for it to both built-in themes, run these commands:

pybabel init --input-file mkdocs/themes/mkdocs/messages.pot --output-dir mkdocs/themes/mkdocs/locales -l es
pybabel init --input-file mkdocs/themes/readthedocs/messages.pot --output-dir mkdocs/themes/readthedocs/locales -l es

The above command will create a file structure as follows:

mkdocs/themes/mkdocs/locales
├── es
│   └── LC_MESSAGES
│       └── messages.po

You can now move on to the next step and add a translation for every text placeholder in the localized catalog.

Updating a theme translation

If a theme's messages.pot template file has been updated since the messages.po was last updated for your locale, follow the steps below to update the theme's messages.po file:

  1. Update the theme's translation catalog to refresh the translatable text placeholders of each theme.
  2. Translate the newly added translatable text placeholders on every messages.po catalog file language you can.
  3. Locally serve and test the translated themes for your language.
  4. Contribute your translation through a Pull Request.

Updating the translation catalogs

This step should be completed after a theme template have been updated for each language that you are comfortable contributing a translation for.

To update the fr translation catalog of both built-in themes, use the following commands:

pybabel update --ignore-obsolete --input-file mkdocs/themes/mkdocs/messages.pot --output-dir mkdocs/themes/mkdocs/locales -l fr
pybabel update --ignore-obsolete --input-file mkdocs/themes/readthedocs/messages.pot --output-dir mkdocs/themes/readthedocs/locales -l fr

You can now move on to the next step and add a translation for every updated text placeholder in the localized catalog.

Translating the MkDocs themes

Now that your localized messages.po files are ready, all you need to do is add a translation in each msgstr item for each msgid item in the file.

msgid "Next"
msgstr "Siguiente"

Warning

Do not modify the msgid as it is common to all translations. Just add its translation in the msgstr item.

Once you have finished translating all of the terms listed in the po file, you'll want to test your localized theme.

Testing theme translations

To test a theme with translations, you need to first compile the messages.po files of your theme into messages.mo files. The following commands will compile the es translation for both built-in themes:

pybabel compile --statistics --directory mkdocs/themes/mkdocs/locales -l es
pybabel compile --statistics --directory mkdocs/themes/readthedocs/locales -l es

The above command results in the following file structure:

mkdocs/themes/mkdocs/locales
├── es
│   └── LC_MESSAGES
│       ├── messages.mo
│       └── messages.po

Note that the compiled messages.mo file was generated based on the messages.po file that you just edited.

Then modify the mkdocs.yml file at the root of the project to test the new and/or updated locale:

theme:
  name: mkdocs
  locale: es

Finally, run mkdocs serve to check out your new localized version of the theme.

Note

The build and release process takes care of compiling and distributing all locales to end users so you only have to worry about contributing the actual text translation messages.po files (the rest is ignored by git).

After you have finished testing your work, be sure to undo the change to the locale setting in the mkdocs.yml file before submitting your changes.

Updating theme documentation

The page Choosing your theme updates by itself with all available locale options.

Contributing translations

It is now time for you to contribute your nice work to the project. Thank you!