Translation guidelines

Zulip’s has full support for Unicode (and partial support for RTL languages), so you can use your preferred language everywhere in Zulip.

Additionally, the Zulip UI is translated into more than a dozen major languages, including Spanish, German, Hindi, French, Chinese, Russian, and Japanese, and we’re always excited to add more. If you speak a language other than English, your help with translating Zulip would be greatly appreciated!

If you are interested in knowing about the technical end-to-end tooling and processes for tagging strings for translation and syncing translations in Zulip, read about Internationalization for Developers.

Translators’ workflow

These are the steps you should follow if you want to help translate Zulip:

  1. Join #translation in the Zulip development community server, and say hello. That stream is also the right place for any questions, updates on your progress, reporting problematic strings, etc.

  2. Sign up for Transifex and ask to join the Zulip project on Transifex, requesting access to any languages that you’d like to contribute to (or add new ones).


    Unless you plan to contribute country-specific translations, do not select a country-specific language in the Languages menu when you sign up. E.g. use English (United Kingdom) if you plan to translate Zulip into UK English, but select Russian rather than Russian (Russia) for general Russian translations.

  3. Wait for a maintainer to approve your Transifex access; this usually takes less than a day. You should then be able to access Zulip’s dashboard in Transifex.

  4. Translate the strings for your language in Transifex. Zulip has several resource files:

    • mobile.json is for the iOS/Android mobile apps.

    • desktop.json is for the parts of the Zulip desktop apps that are not shared with the Zulip web app.

    • django.po and translations.json have strings for the next major release of the Zulip server and web app (which is what we run on and Zulip Cloud).

    • The variants of django.po and translations.json with names starting with a version, like 5-x--, are strings for Zulip’s current stable release series.

    Transifex is smart about only asking you to translate a string once even if it appears in multiple resources. The 5-x-- type variants allow translators to get a language to 100% translated for the current release.

  5. If possible, test your translations (details below).

  6. Ask in Zulip for a maintainer to sync the strings from Transifex, merge them to main, and deploy the update to so you can verify them in action there.

Some useful tips for your translating journey:

  • Follow your language’s translation guide. Keeping it open in a tab while translating is very handy. If one doesn’t exist one, write one as you go; they’re easiest to write as you go along and will help any future translators a lot.

  • Don’t translate variables or code (usually preceded by a %, inside HTML tags <...>, or enclosed in braces like {variable}); just keep them verbatim.

  • When context is unclear, you may find GitHub search helpful for finding the code using a given string (ignore .po and .json matches, and note the search box is semi-invisible in the upper-left corner of the page), or looking at the “Occurrences” section in the Transifex UI, browsing to the file on GitHub, and then searching for the string with Ctrl+F in your browser.

  • When in doubt, ask for context in #translation in the Zulip development community server.

  • If there are multiple possible translations for a term, search for it in the Concordance tool (the button with a magnet in the top right corner).

    It will show if anyone translated that term before, so we can achieve good consistency with all the translations, no matter who makes them.

  • Pay attention to capital letters and punctuation. Details make the difference!

  • Take advantage of the hotkeys the Transifex Web Editor provides, such as Tab for saving and going to the next string.

  • While one should definitely prioritize translating translations.json, since the most prominent user-facing strings are there, API error messages in django.po are presented to users, so a full translation should include them.

Testing translations

This section assumes you have a Zulip development environment set up; if setting one up is a problem for you, ask in and we can usually just deploy the latest translations there.

  • First, download the updated resource files from Transifex using the tools/i18n/sync-translations command (it will require some initial setup). This command will download the resource files from Transifex and replace your local resource files with them, and then compile them. You can now test your translation work in the Zulip UI.

There are a few ways to see your translations in the Zulip UI:

  • You can insert the language code as a URL prefix. For example, you can view the login page in German using http://localhost:9991/de/login/. This works for any part of the Zulip UI, including portico (logged-out) pages.

  • For Zulip’s logged-in UI (i.e. the actual web app), you can pick the language in the Zulip UI.

  • If your system has languages configured in your OS/browser, Zulip’s portico (logged-out) pages will automatically use your configured language. Note that we only tag for translation strings in pages that individual users need to use (e.g. /login/, /register/, etc.), not marketing pages like /features/.

  • In case you need to understand how the above interact, Zulip figures out the language the user requests in a browser using the following prioritization (mostly copied from the Django docs):

    1. It looks for the language code as a URL prefix (e.g. /de/login/).

    2. It looks for the cookie named ‘django_language’. You can set a different name through the LANGUAGE_COOKIE_NAME setting.

    3. It looks for the Accept-Language HTTP header in the HTTP request (this is how browsers tell Zulip about the OS/browser language).

  • Using an HTTP client library like requests, cURL or urllib, you can pass the Accept-Language header; here is some sample code to test Accept-Language header using Python and requests:

    import requests
    headers = {"Accept-Language": "de"}
    response = requests.get("http://localhost:9991/login/", headers=headers)

    This can occasionally be useful for debugging.

Machine translation

Transifex has built-in machine translation capabilities. If machine translation is enabled for your language, you can generate one by clicking the lightning symbol above the translation box.

Transifex machine translation button

There are a few things to keep in mind if you choose to make use of machine translation:

  • We expect human-quality translations for Zulip. While machine translation can be a helpful aid, please be sure to review all machine translated strings.

  • We are using machine translation in HTML mode, which has a known bug that causes special characters to be rendered as their HTML encodings. For example, a ' will be converted to &#39;. Please be sure to fix this when reviewing translations.

Translation style guides

We maintain translation style guides for Zulip, giving guidance on how Zulip should be translated into specific languages (e.g. what word to translate words like “stream” to), with reasoning, so that future translators can understand and preserve those decisions:

Some translated languages don’t have these, but we highly encourage translators for new languages (or those updating a language) write a style guide as they work, since it’s easy to take notes as you translate, and doing so greatly increases the ability of future translators to update the translations in a consistent way. See our docs on this documentation for how to submit your changes.


We expect that all the English translatable strings in Zulip are properly capitalized in a way consistent with how Zulip does capitalization in general. This means that:

  • The first letter of a sentence or phrase should be capitalized.

    • Correct: “Stream settings”

    • Incorrect: “Stream Settings”

  • All proper nouns should be capitalized.

    • Correct: “This is Zulip”

    • Incorrect: “This is zulip”

  • All common words like URL, HTTP, etc. should be written in their standard forms.

    • Correct: “URL”

    • Incorrect: “Url”

The Zulip test suite enforces these capitalization guidelines in the web app codebase in our test suite (./tools/check-capitalization; tools/lib/ has some exclude lists, e.g. IGNORED_PHRASES).