Technology comparison
Paraglide vs react-i18next: compile-time vs runtime i18n
Paraglide is smaller and stricter. react-i18next is bigger and more forgiving.
2026-07-01
My i18n migration experience: - react-i18next: Used for 2 years, bundle too large, poor type experience - Paraglide JS: Migrated in 2024, bundle reduced 40KB, type-safe Migration took 1 day, but since then every translation rename triggers TS errors — this is a huge DX improvement. Below, I'll explain the migration ROI in detail.
TL;DR
- Pick Paraglide for bundle size, type safety, and tree-shakable translations.
- Pick react-i18next for maturity, ecosystem plugins, and runtime flexibility.
| Dimension | Paraglide JS | react-i18next |
|---|---|---|
| Approach | Compile-time | Runtime |
| Bundle overhead | ~0 KB (tree-shakable) | ~40 KB core + resources |
| Type safety | Full | Add-on |
| Ecosystem age | Newer | Very mature |
| Plurals / ICU | Yes | Yes |
| Framework support | React, Svelte, Vue, more | React-focused |
Bundle economics
Paraglide compiles translations into individual functions. Unused keys never ship.
react-i18next ships the runtime plus your entire message bundle for the loaded locale.
Type safety
Paraglide types every key. Renaming a message triggers TS errors across the codebase.
react-i18next's TS story requires opt-in and manual maintenance.
Where TanStack Ship fits
TanStack Ship uses Paraglide JS for its trilingual (en/zh/de) i18n — bundle-friendly, type-safe, tree-shakable. If you've read this and want to try Paraglide in a real SaaS without wiring it up yourself, TanStack Ship ships with it configured correctly, including hreflang tags and localized routes.
Frequently asked questions
Which is smaller?
Paraglide.
Which is more mature?
react-i18next.
Which is more type-safe?
Paraglide.
Which for a multi-framework project?
Paraglide.
Which for Next.js specifically?
Both work; react-i18next has more Next.js-specific tutorials.
Related Links
Ready to see TanStack Ship in action?
Ship a paid SaaS on TanStack Start with UTM attribution, MRR dashboards, and 14 growth modules built in — from $99.