Internationalization (i18n) Packages
Internationalization and localization libraries for translating, formatting, and adapting applications to different languages and regions (i18next, FormatJS).
Packages in Internationalization (i18n)
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i18next
The internationalization framework for JavaScript, with zero runtime dependencies and a pluggable ecosystem for every environment.
react-i18next
React bindings for the i18next internationalization ecosystem, built on hooks and a translation-aware Trans component.
Day.js
A 2KB immutable JavaScript date-time library with a Moment.js-compatible API
Moment.js
Parse, validate, manipulate, and display dates in JavaScript with a chainable API.
i18next-browser-languageDetector
Detects a visitor's language from cookies, storage, the URL, or the browser itself and wires it straight into i18next.
vue-i18n
The internationalization plugin that brings translations, pluralization, and locale-aware formatting to Vue.js 3 apps.
i18next-http-backend
An i18next backend plugin that loads translation resources over HTTP using fetch or XMLHttpRequest, for Node.js, browsers, and Deno.
idna
Internationalized Domain Names for Python — IDNA 2008 and UTS #46 encoding and decoding
slugify
Slugify a string with accurate Unicode transliteration for URLs, filenames, and IDs.
i18next-resources-to-backend
Turns any loader function or static resource object into a fully-formed i18next backend, so translations can be lazy-loaded via dynamic import() in Node.js, browsers, and Deno.
Lingui
A readable, 2kb internationalization runtime for JavaScript with ICU MessageFormat and rich-text support.
React Intl
React components and hooks for internationalizing apps with locale-aware dates, numbers, lists, and pluralized, translated messages.
next-intl
Type-safe internationalization for Next.js, built for App Router, Server Components, and static rendering.
eslint-plugin-i18next
An ESLint plugin that catches hardcoded, non-localized strings in JSX, Vue templates, and TypeScript before they ship.
Babel
The Python internationalization library for locale-aware dates, numbers, and message catalogs
encoding_rs
Fast, WHATWG-compliant character encoding conversion crate that powers Firefox's Web-facing text decoding.
unicode-normalization
Unicode NFC/NFD/NFKC/NFKD normalization for Rust strings, per UAX #15
react-timeago
A tiny React component that renders live, self-updating relative timestamps like "5 minutes ago".
unicode-segmentation
Split Rust strings into grapheme clusters, words, and sentences per Unicode UAX #29
phonenumbers
Python port of Google's libphonenumber for parsing, validating, and formatting phone numbers from over 200 countries and regions.
slug
Turns any Unicode string into a clean, URL- and filename-safe ASCII slug, with built-in transliteration for over 20 languages.
@intlify/unplugin-vue-i18n
A build-time unplugin that precompiles Vue I18n locale messages into optimized JavaScript across Vite, Webpack, and Rspack.
pinyin-pro
Fast, high-accuracy Chinese-to-pinyin conversion library with tone, initial/final, and text-matching support.
Nuxt I18n
Internationalization module for Nuxt that generates locale-prefixed routes, lazy-loads translation messages, and wires up per-locale SEO automatically.