🪂 Paraglide JS

Compiler-based i18n library with tree-shaking, full typesafety, and near zero runtime

Paraglide JS compiles your translations into tree-shakable message functions.
Unused translations are eliminated, and what remains is a fully typesafe API with autocomplete.

Documentation · Quick Start · Report Bug

<sub>Used in production by

                ...and more</sub>

_{Trusted by framework authors}

Svelte's official i18n recommendation
Part of TanStack's CI pipeline

Code Preview

// messages/en.json
{
  "greeting": "Hello {name}!"
}

import { m } from "./paraglide/messages.js"

m.greeting({ name: "World" })  // "Hello World!" — fully typesafe

The compiler generates typed message functions. Your bundler tree-shakes unused messages. Expect ~75% smaller bundles (47 KB vs 205 KB) compared to runtime i18n libraries. See benchmarks →

Why Paraglide?

Tiny Runtime	~300 bytes. No async loading. No waterfalls.
Tree-Shakable	Unused messages are eliminated by your bundler.
Fully Typesafe	Autocomplete for message keys and parameters. Typos become compile errors.
Framework Agnostic	Works with React, Vue, Svelte, Solid, TanStack, or vanilla JS/TS.
Built-in i18n Routing	URL-based locale detection and localized paths out of the box.
Inlang Ecosystem	VS Code extension, CLI, translation editor — all work out of the box.

Works With Your Stack

React · Vue · TanStack Start · SvelteKit · Next.js · Astro · Vanilla JS/TS

Quick Start

npx @inlang/paraglide-js init

The CLI sets up everything:

• Creates your message files
• Configures your bundler (Vite, Webpack, etc.)
• Generates typesafe message functions

Then use your messages:

import { m } from "./paraglide/messages.js"
import { setLocale, getLocale } from "./paraglide/runtime.js"

// Use messages (typesafe, with autocomplete)
m.hello_world()
m.greeting({ name: "Ada" })

// Get/set locale
getLocale()      // "en"
setLocale("de")  // switches to German

Full Getting Started Guide →

How It Works

messages/en.json  ──┐
messages/de.json  ──┼──→  Compiler  ──→  ./paraglide/messages.js
messages/fr.json  ──┘                    ./paraglide/runtime.js

1. You write messages in JSON (or any supported format)
2. The compiler generates typed functions
3. Your bundler tree-shakes unused messages
4. Result: tiny, typesafe, fast

Message Format

Paraglide uses Intl.PluralRules for locale-aware pluralization, supporting all CLDR plural categories (zero, one, two, few, many, other) and ordinals (1st, 2nd, 3rd). Gender and custom selects are supported via the variants system.

// Pluralization example
m.items_in_cart({ count: 1 })  // "1 item in cart"
m.items_in_cart({ count: 5 })  // "5 items in cart"

// Works correctly for complex locales (Russian, Arabic, etc.)

Message format is plugin-based — use the default inlang format, or switch to i18next, JSON, or ICU MessageFormat via plugins.

Pluralization & Variants Docs →

Comparison

Feature	Paraglide	i18next	react-intl
Runtime size	~300B	10kB+	8kB+
Tree-shakable	✅	❌	❌
Typesafe	✅	Partial	❌
Framework agnostic	✅	Wrappers needed	React only
i18n routing	✅ Built-in	❌	❌

Full Comparison →

What Developers Say

"Paraglide JS is by far the best option when it comes to internationalization. Nothing better on the market."

Ancient-Background17 · Reddit

"Just tried Paraglide JS. This is how i18n should be done! Totally new level of DX."

Patrik Engborg · @patrikengborg

"I was messing with various i18n frameworks and must say Paraglide was the smoothest experience. SSG and SSR worked out of the box."

Dalibor Hon · Discord

Talks

• Paraglide JS 1.0 announcement
• Svelte London January 2024 Meetup

Ecosystem

Paraglide is built on the open inlang format. Works with:

Tool	Description
Sherlock	VS Code extension for inline translation editing
CLI	Machine translate from the terminal
Fink	Translation editor for non-developers
Parrot	Manage translations in Figma

Explore the inlang ecosystem →

Documentation

• Getting Started
• Framework Guides (Next.js, SvelteKit, Astro, etc.)
• Message Syntax & Pluralization
• Routing & SSR
• API Reference

Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

• GitHub Issues
• Discord Community

License

MIT — see LICENSE