When building a React app that supports multiple languages, following best practices ensures scalability and maintainability:

1. Plan internationalization early
   It’s much harder to retrofit i18n after building the app. Think about translations, formats, and layouts from the start.

2. Use keys, not hardcoded strings
   Always use keys for translatable strings. Avoid hardcoding text inside components.

3. Organize translation files properly

   • Group keys logically (e.g., homepage, profile, errors).
   • Keep JSON files clean and modular.

4. Support dynamic language switching
   Allow users to change their language preference without reloading the app.

5. Handle pluralization and gender properly
   Different languages have complex rules. Use libraries that support plural forms and gender-specific translations.

6. Use fallback languages
   Always configure a default language if a translation is missing.

7. Optimize for performance

   • Lazy-load translations for better initial load times.
   • Avoid loading all languages at once if not necessary.

8. Account for text direction (RTL support)
   Arabic, Hebrew, and similar languages require right-to-left (RTL) layout adjustments.

9. Internationalize all user-visible text
   This includes validation messages, tooltips, error screens, modals, etc.

10. Test thoroughly in all languages
    Ensure UI layouts, text overflows, and alignment work properly for every supported language.

By following these best practices, you can create a truly global React application that feels natural and professional to users from different regions.

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