i18next plus react-i18next replace the core i18n shim in src/lib/i18n.ts, keeping exactly the same surface your screens already use: i18n.t(key, vars) and useT(). I'd pick it when you want the ecosystem - plurals, formatters, ICU add-ons, and translators who already know the format. Pick lingui if you'd rather have a CLI-driven catalog workflow, and none while you're still English-only. Keys are the English source strings, so a screen reads identically with or without this module.
When to pick i18next
i18next: The default. Pick it for the bigger ecosystem: plurals, formatters, translators who already know the format.
At a glance
- Runs in Expo Go
- Yes
- Files added
- 10
- npm packages
- 3
- Keys to paste
- None
- Included in
- Starter and Pro
- Tests included
- 1
Set it up
bun run setup --i18n i18nextSetup copies the module in, installs SDK-matched versions and removes the options you did not pick. Then bun run doctor lists every key still missing, with a link to where you get it. The step-by-step guide is in the i18next docs.
Wiring it by hand instead? Read the guide: Expo i18n: i18next or Lingui, compared.
i18next vs other i18n options
| Option | Expo Go | npm packages | Keys to paste | Included in |
|---|---|---|---|---|
| i18next | Yes | 3 | 0 | Starter and Pro |
| Lingui | Yes | 4 | 0 | Starter and Pro |
Questions
Can I use i18next in Expo Go?
Yes. This module runs in Expo Go, so you can try it before you make a development build.
What do I need to set up i18next in an Expo app?
Only bun run setup --i18n i18next. There are no API keys to paste; bun run doctor checks the result.
Which other modules does i18next need?
It needs a Storage option (expo-sqlite/kv-store, MMKV or AsyncStorage). Pick those in the same setup run.
Does the ReadyNative free tier include i18next?
No. It ships in Starter and Pro (one payment, lifetime updates); the free tier ships with i18n switched off.
Can I build the app without i18next?
Yes. Pick none for i18n (bun run setup --i18n none) - i18n.t/useT return the English key.
i18next or Lingui for Expo?
i18next: The default. Pick it for the bigger ecosystem: plurals, formatters, translators who already know the format. Lingui: Pick it for ICU messages and a catalog CLI (bun run i18n:extract).
Which i18next version does it install?
For Expo SDK 57: expo-localization ~57.0.2, i18next ^26.4.2, react-i18next ^17.0.15. Setup installs Expo packages with expo install, so they match the SDK.
Get it
i18next ships in Starter and Pro: one payment, lifetime updates. See pricing or browse every module.