Flutter Internationalization Best Practices
Flutter handles internationalization through ARB (Application Resource Bundle) files and the intl package. Unlike iOS and Android where translations are runtime lookups, Flutter generates type-safe Dart code from your ARB files at compile time. This catches missing translations before your app ships. Here is how to set it up correctly.
Setting up Flutter l10n
Add flutter_localizations
Add to pubspec.yaml dependencies.
Create l10n.yaml
Set arb-dir, template-arb-file, output-localization-file.
Create template ARB file
Create lib/l10n/app_en.arb with English strings.
Configure MaterialApp
Set localizationsDelegates and supportedLocales.
final l10n = AppLocalizations.of(context);
Text(l10n.appTitle)Type Safety
Flutter's codegen creates type-safe methods. Compiler catches missing translations at build time.
We stopped shipping untranslated strings entirely with LocaleKit managing our ARB files.
FAQ
intl package needed?
For basic translations, flutter_localizations alone is sufficient.
Stop managing translation files manually
LocaleKit detects, translates, and syncs all your localization files — iOS, Android, Flutter, and more. Everything runs locally on your machine.
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