🪂 Paraglide JS

Compiler-based i18n library that emits tree-shakable translations, leading to up to 70% smaller i18n bundle sizes.

Documentation · Quick Start · Report Bug

<sub>Used in production by

                ...and more</sub>

_{Trusted by framework authors}

SvelteKit's official i18n integration
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 up to 70% smaller i18n bundle sizes compared to runtime i18n libraries (e.g. 47 KB vs 205 KB).

Why Paraglide?

Smaller i18n Bundle	Up to 70% smaller i18n bundle size than runtime i18n libraries.
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.
Built on inlang	Integrates with Sherlock (VS Code extension), Fink (translation editor), and more.

Works With Your Stack

React · Vue · TanStack Start · SvelteKit · React Router · Astro · Vanilla JS/TS

Tip

Paraglide is ideal for any Vite based app. Setup is just one plugin and Vite's tree-shaking eliminates unused messages automatically. Get started →

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

Paraglide compiles an inlang project into tree-shakable message functions. Your bundler eliminates unused messages at build time.

       ┌────────────────┐
       │ Inlang Project │
       └───────┬────────┘
               │
               ▼
  ┌────────────────────────┐
  │  Paraglide Compiler    │
  └───────────┬────────────┘
              │
              ▼
 ┌──────────────────────────┐
 │ ./paraglide/messages.js  │
 │ ./paraglide/runtime.js   │
 └──────────────────────────┘

Watch: How Paraglide JS works in 6 minutes →

Message Format

Paraglide supports locale-aware formatting via declaration formatters:

• plural (Intl.PluralRules) for plural and ordinal categories
• number (Intl.NumberFormat) for numbers, currency, compact notation, and more
• datetime (Intl.DateTimeFormat) for dates/times with locale-aware output

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. If your team relies on ICU MessageFormat 1 syntax, use the inlang-icu-messageformat-1 plugin.

Formatting Docs → · Pluralization & Variants Docs →

Comparison

Feature	Paraglide	i18next	react-intl
i18n bundle size	Up to 70% smaller via tree-shaking	❌ Ships all messages	❌ Ships all messages
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

"I migrated from i18next. Paraglide reduced my i18n bundle from 40KB to ~2KB."

Daniel · Why I Replaced i18next with Paraglide JS

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 (React Router, SvelteKit, Astro, etc.)
• Message Syntax & Pluralization
• Formatting (Number/Date)
• Routing & SSR
• API Reference

Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

• GitHub Issues
• Discord Community

License

MIT — see LICENSE