BabelFish - human friendly i18n for JS

Internationalization with easy syntax for node.js and browser.

Classic solutions use multiple phrases for plurals. Babelfish defines plurals inline instead - that's more compact, and easy for programmers. Also, phrases are grouped into nested scopes, like in Ruby.

BabelFish supports all plural rules from unicode CLDR (via plurals-cldr).



$ npm install babelfish


$ bower install babelfish

Use es5-shim for old browsers compatibility.

Phrases Syntax

  • #{varname} Echoes value of variable
  • ((Singular|Plural1|Plural2)):count Plural form


  • А у меня в кармане #{nails_count} ((гвоздь|гвоздя|гвоздей)):nails_count

You can also omit anchor variable for plurals, by default it will be count. Thus following variants are equal:

  • I have #{count} ((nail|nails))
  • I have #{count} ((nail|nails)):count

Also you can use variables in plural parts:

  • I have ((#{count} nail|#{count} nails))

Need special zero form or overwrite any specific value? No problems:

  • I have ((=0 no nails|#{count} nail|#{count} nails))
Escape chars

If you need #{, ((, | or )) somewhere in text, where it can be considered as markup part - just escape them with \.

Example with YAML

As BabelFish flatten scopes, it's really fun and nice to store translations in YAML files:

  profile: Профиль
  forums: Форумы
      new_topic: Новая тема
        title : Последнее сообщение
        by : от
    apples: "На столе лежит #{count} ((яблоко|яблока|яблок))"


// Create new instance of BabelFish with default language/locale: 'en-GB'
var BabelFish = require('babelfish');
var i18n = new BabelFish('en-GB');

// Fill in some phrases
i18n.addPhrase('en-GB', 'demo.hello',         'Hello, #{}.');
i18n.addPhrase('en-GB', 'demo.conv.wazup',    'Whats up?');
i18n.addPhrase('en-GB', 'demo.conv.alright',  'Alright, man!');
i18n.addPhrase('en-GB', 'demo.coerce',        'Total: #{count}.');

i18n.addPhrase('ru-RU', 'demo.hello',         'Привет, #{}.');
i18n.addPhrase('ru-RU', 'demo.conv.wazup',    'Как дела?');

i18n.addPhrase('uk-UA', 'demo.hello',         'Здоровенькі були, #{}.');

// Set locale fallback to use the most appropriate translation when possible
i18n.setFallback('uk-UA', 'ru-RU');

// Translate
var params = {user: {name: 'ixti'}};

i18n.t('ru-RU', 'demo.hello', params);  // -> 'Привет, ixti.'
i18n.t('ru-RU', 'demo.conv.wazup');     // -> 'Как дела?'
i18n.t('ru-RU', 'demo.conv.alright');   // -> 'Alright, man!'

i18n.t('uk-UA', 'demo.hello', params);  // -> 'Здоровенькі були, ixti.'
i18n.t('uk-UA', 'demo.conv.wazup');     // -> 'Как дела?'
i18n.t('uk-UA', 'demo.conv.alright');   // -> 'Alright, man!'

// When params is number or strings, it will be coerced to
// `{ count: XXX, value: XXX }` - use any of those in phrase.
i18n.t('en-GB', 'demo.coerce', 5);      // -> 'Total: 5.'

// You may wish to "dump" translations to load in browser later
// Dump will include all fallback translations and fallback rules
var locale_dump = i18n.stringify('ru-RU');

var i18n_new = require('babelfish')('en-GB'); // init without `new` also works

// Use objects instead of strings (object/array/number/boolean) - can be
// useful to prepare bulk data for external libraries.
// Note, only JSON-supported types are ok (no date & regex)
i18n.addPhrase('en-GB', 'demo.boolean',  true);
i18n.addPhrase('en-GB', 'demo.number',   123);
i18n.addPhrase('en-GB', 'demo.array',    [1, 2, 3]);
// fourth param required for hashes (objects) to disable flattening,
// other types are autodetected
i18n.addPhrase('en-GB', 'demo.array',    { foo:1, bar:"2" }, false);

Implementations in other languages


View the LICENSE file (MIT).