projectfluent/fluent.js

JavaScript implementation of Project Fluent

JavaScript

1,011

2,305 commits

updated May 22, 2026

See the code

README

Project Fluent

Fluent.js is a JavaScript implementation of Project Fluent, a localization framework designed to unleash the expressive power of the natural language.

Project Fluent keeps simple things simple and makes complex things possible. The syntax used for describing translations is easy to read and understand. At the same time it allows, when necessary, to represent complex concepts from natural languages like gender, plurals, conjugations, and others.

Packages

Fluent.js consists of a set of packages which have different use-cases and can be installed independently of each other.

You can install each of the above packages via npm, e.g. npm install @fluent/react.
See the end of this README for instructions on how to build fluent.js locally.

Learn the FTL syntax

FTL is a localization file format used for describing translation resources. FTL stands for Fluent Translation List.

FTL is designed to be simple to read, but at the same time allows to represent complex concepts from natural languages like gender, plurals, conjugations, and others.

hello-user = Hello, { $username }!

Read the Fluent Syntax Guide in order to learn more about the syntax. If you're a tool author you may be interested in the formal EBNF grammar.

Discuss

We'd love to hear your thoughts on Project Fluent! 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!

Get Involved

Fluent.js 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.

Local Development

Hacking on fluent.js is easy! To quickly get started clone the repo:

$ git clone https://github.com/projectfluent/fluent.js.git
$ cd fluent.js

You'll need at least Node.js 20.19. Older versions are not supported.

Install the dependencies used by all packages, which are managed as npm workspaces:

$ npm install

Build and test all packages at once:

$ npm run dist

…which is equivalent to:

$ npm run clean
$ npm run build --workspaces
$ npm run lint
$ npm run test
$ npm run docs

Each package may also be built separately by running npm run build in its directory.

formatting
ftl
globalization
i18n
internationalization
l10n
language
language-negotiation
locale
localization
react
translation

projectfluent/fluent.js

JavaScript implementation of Project Fluent

JavaScript

1,011

2,305 commits

updated May 22, 2026

See the code

README

Project Fluent

Fluent.js is a JavaScript implementation of Project Fluent, a localization framework designed to unleash the expressive power of the natural language.

Project Fluent keeps simple things simple and makes complex things possible. The syntax used for describing translations is easy to read and understand. At the same time it allows, when necessary, to represent complex concepts from natural languages like gender, plurals, conjugations, and others.

Packages

Fluent.js consists of a set of packages which have different use-cases and can be installed independently of each other.

You can install each of the above packages via npm, e.g. npm install @fluent/react.
See the end of this README for instructions on how to build fluent.js locally.

Learn the FTL syntax

FTL is a localization file format used for describing translation resources. FTL stands for Fluent Translation List.

FTL is designed to be simple to read, but at the same time allows to represent complex concepts from natural languages like gender, plurals, conjugations, and others.

hello-user = Hello, { $username }!

Read the Fluent Syntax Guide in order to learn more about the syntax. If you're a tool author you may be interested in the formal EBNF grammar.

Discuss

We'd love to hear your thoughts on Project Fluent! 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!

Get Involved

Fluent.js 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.

Local Development

Hacking on fluent.js is easy! To quickly get started clone the repo:

$ git clone https://github.com/projectfluent/fluent.js.git
$ cd fluent.js

You'll need at least Node.js 20.19. Older versions are not supported.

Install the dependencies used by all packages, which are managed as npm workspaces:

$ npm install

Build and test all packages at once:

$ npm run dist

…which is equivalent to:

$ npm run clean
$ npm run build --workspaces
$ npm run lint
$ npm run test
$ npm run docs

Each package may also be built separately by running npm run build in its directory.

formatting
ftl
globalization
i18n
internationalization
l10n
language
language-negotiation
locale
localization
react
translation

Project health

Overall

3.6/10

Maintained

0/10

Code review

6/10
OpenSSF Scorecard

Latest release

0.13.0 · Jul 25, 2019

Releases this year

0
Deprecated

Significant stargazers

(top 24 of 35)

Nick Schonning

713 followers · starred Jun 2019

Tobias Bieniek

713 followers · starred May 2019

snek

1,044 followers · starred Jan 2020

Toru Nagashima

1,172 followers · starred Apr 2019