Quick Start Guide

This guide will walk you through the basic steps to add rails-i18n to a new Rails application and see it in action.

1. Create a New Rails App

If you don't have one already, create a new Rails application.

rails new my_i18n_app
cd my_i18n_app

2. Add rails-i18n to your Gemfile

Open your Gemfile and add the gem. For a Rails 8 app, this would be:

gem 'rails-i18n', '~> 8.0.0'

Then, run the bundler from your terminal:

bundle install

3. Configure the Default Locale

Let's set the application's default language to German (de). In config/application.rb, add the following line inside the Application class:

module MyI18nApp
  class Application < Rails::Application
    # ... other configurations ...

    # Set the default locale to German
    config.i18n.default_locale = :de
  end
end

4. Use a Translated Helper in a View

Generate a simple controller and view to see the translations.

rails generate controller welcome index

Now, open app/views/welcome/index.html.erb and add a Rails helper that uses a translated string. For example, let's display the text for a "Create" button.

<h1>Willkommen!</h1>

<p>
  <strong>English Button Text:</strong>
  <%= I18n.with_locale(:en) { t('helpers.submit.create', model: 'Article') } %>
</p>

<p>
  <strong>German Button Text (Default Locale):</strong>
  <%= t('helpers.submit.create', model: 'Artikel') %>
</p>

5. Start the Server and View the Results

Start your Rails server:

rails server

Navigate to http://localhost:3000/welcome/index in your browser. You should see the following output:

English Button Text: Create Article

German Button Text (Default Locale): Artikel erstellen

This confirms that rails-i18n is successfully providing the German translations for your application.