How to translate Sumatra PDF

If you want to see Sumatra PDF translated to your language, you can make it happen.

First important note: the file must be saved with utf8 encoding with BOM mark. If it's saved in a different encoding, it'll be unusable. Please use e.g. free notepad2 (menu File\Encoding\UTF-8 with signature).

Second important note: please really read the first important note. It's really that important. I've already had several translations submitted that were not saved in the right format.

Each language has a separate translation file. It's format is very simple: english string followed by translation followed by an empty line. For example, part of file with German translation might look like:



Lines that begin with "#" are comments. At the end of the file is a list of (commented out) strings that are not translated in this language.

Here's a table of all languages:

To contribute to a translation:

  • grab the latest version of strings file for your language, either by downloading the file using a link above or checking out the sources
  • add and improve translations for the language you know well
  • e-mail me a modified file

Few notes

Keep in mind that translation is an on-going process. During development new strings are being added and they'll need to be translated. Before releasing a new version I plan to ask for help translating new strings on the forum

Don't worry if you don't have the time to translate all of the strings at once. Even one translated string is better than nothing, so do send me even incomplete translations.

How can you test the translations?

If you can't build Sumatra PDF from sources, then you're out of luck. You have to send me the translations without testing and wait for a new release.

If you can build Sumatra PDF, you can rebuild program with new translations. It's very simple:

  • change strings-*.txt file for your language
  • run python update_translations.pyin src directory
  • rebuild the program


Current translations has been contributed by many people.

Krzysztof Kowalczyk