---

name: laravel-i18n description: Laravel localization - __(), trans_choice(), lang files, JSON translations, pluralization. Use when implementing translations in Laravel apps. user-invocable: false

Laravel Internationalization

Setup

Copyphp artisan lang:publish

Creates lang/ directory with default language files.

---

File Structure

Copylang/
├── en/
│   ├── messages.php      # Short keys
│   └── validation.php
├── fr/
│   ├── messages.php
│   └── validation.php
├── en.json               # Full text keys
└── fr.json

---

Configuration

Copy// config/app.php
'locale' => env('APP_LOCALE', 'en'),
'fallback_locale' => env('APP_FALLBACK_LOCALE', 'en'),

---

Translation Helpers

Copy// Basic translation
__('messages.welcome')

// With replacement
__('Hello :name', ['name' => 'John'])

// JSON approach (full text as key)
__('Welcome to our application')

// Alias
trans('messages.welcome')

---

PHP Translation Files

Copy// lang/en/messages.php
return [
    'welcome' => 'Welcome to our application',
    'hello' => 'Hello :name',
    'goodbye' => 'Goodbye :name, see you :time',
];

---

JSON Translation Files

Copy// lang/fr.json
{
    "Welcome to our application": "Bienvenue sur notre application",
    "Hello :name": "Bonjour :name"
}

---

Pluralization

Copy// lang/en/messages.php
'apples' => '{0} No apples|{1} One apple|[2,*] :count apples',

Copytrans_choice('messages.apples', 0);  // "No apples"
trans_choice('messages.apples', 1);  // "One apple"
trans_choice('messages.apples', 5);  // "5 apples"

---

Runtime Locale

Copyuse Illuminate\Support\Facades\App;

// Set locale
App::setLocale('fr');

// Get current locale
$locale = App::currentLocale();

// Check locale
if (App::isLocale('fr')) {
    // ...
}

---

Middleware Example

Copy// app/Http/Middleware/SetLocale.php
public function handle(Request $request, Closure $next): Response
{
    $locale = $request->segment(1);

    if (in_array($locale, ['en', 'fr', 'de'])) {
        App::setLocale($locale);
    }

    return $next($request);
}

---

Blade Usage

Copy{{ __('messages.welcome') }}
@lang('messages.welcome')
{{ trans_choice('messages.apples', 5) }}

---

Best Practices

1. Use JSON files for large apps with many strings
2. PHP files for structured, nested translations
3. Always use placeholders :name not concatenation
4. Group by feature in namespaces: auth.login.title