A natural-language localization framework

L20n: Localization 2.0

L20n reinvents software localization. Users should be able to benefit from the entire expressive power of a natural language. L20n keeps simple things simple, and at the same time makes complex things possible.

A straight-forward example in English:

<brandName "Firefox">
<about "About {{ brandName }}">
<preferences "{{ brandName }} Preferences">

And the same thing in Polish:

<brandName {
  nominative: "Firefox",
  genitive: "Firefoksa",
  dative: "Firefoksowi",
  accusative: "Firefoksa",
  instrumental: "Firefoksem",
  locative: "Firefoksie"
<about "O {{ brandName.locative }}">
<preferences "Preferencje {{ brandName.genitive }}">

Visit L20n by Example to learn more about L20n's syntax.

You can take advantage of HTML bindings to localize your HTML documents with L20n. See docs/html for documentation and examples.

L20n encloses localization into so-called contexts. A context is an independent object with its own set of localization resources and available languages. You can have more than one context at the same time.

var ctx = L20n.getContext();

When you freeze the context by calling requestLocales, the resource files will be retrieved, parsed and compiled. You can listen to the ready event (emitted by the Context instance when all the resources have been compiled) and use ctx.getSync and ctx.getEntitySync to get translations synchronously.

Alternatively, you can register callbacks to execute when the context is ready (or when globals change and translations need to be updated) with ctx.localize.

ctx.localize(['hello', 'new'], function(l10n) {
  var node = document.querySelector('[data-l10n-id=hello]');
  node.textContent = l10n.entities.hello.value;

You can find the complete documentation for localizers, developers and contributors at the Mozilla Developer Network. The original design documents can be found at the Mozilla Wiki. We also use the wiki for release planning.

We'd love to hear your thoughts on L20n! Whether you're a localizer looking for a better way to express yourself in your language, or a developer trying to make your app localizable and multilingual, or a hacker looking for a project to contribute to, please do get in touch on the mailing list and the IRC channel.

L20n is open-source, licensed under the Apache License, Version 2.0. We encourage everyone to take a look at our code and we'll listen to your feedback.

We use Bugzilla to track our work. Visit our Tracking page for a collection of useful links and information about our release planning. You can also go straight to the Dashboard or file a new bug.

We <3 GitHub, but we prefer text/plain patches over pull requests. Refer to the Contributor's documentation for more information.