next-intl

next-intl is an internationalization library tailored for Next.js (App Router and Pages): message catalogs, locale-aware routing hooks, and formatting helpers without bolting on a separate i18n framework by hand. It pairs well with static or server-rendered Next apps where you need locale prefixes, translated strings, and type-safe message keys. For non-Next React apps, other i18n stacks are usually a better fit.