Vue 3 i18n Installation Guide

Hey guys! So, you’re diving into the awesome world of Vue 3 and want to make your app accessible to a global audience? That’s fantastic! Internationalization, or i18n as we cool cats call it, is super important for reaching more users. Today, we’re going to walk through the install i18n vue 3 process, step-by-step. We’ll make sure you’ve got everything set up so you can start translating your app like a pro. Get ready, because this is going to be a breeze!

Getting Started with Vue 3 i18n

Alright, let’s kick things off with the basics of getting i18n up and running in your Vue 3 project. The most popular and robust library for this is vue-i18n . It’s a powerful tool that makes managing translations incredibly straightforward. Before we even think about installing anything, you should have a Vue 3 project already set up. If you don’t, you can easily create one using Vue CLI or Vite. Just hop onto your terminal and run npm create vue@latest or yarn create vue if you’re a Yarn fan. Once your project is humming along, we can proceed with integrating vue-i18n . The first crucial step in install i18n vue 3 is adding the library to your project’s dependencies. You’ll typically do this using your package manager. Open up your terminal in the root directory of your Vue 3 project and execute the following command:

npm install vue-i18n@next

Or, if you prefer Yarn:

yarn add vue-i18n@next

Why @next ? You might be wondering why we’re specifying @next . This is because vue-i18n has a specific version that’s compatible with Vue 3. The next tag usually points to the latest stable version that supports the newest Vue features. It’s always a good idea to check the official vue-i18n documentation for the absolute latest compatibility information, but for now, @next is your best bet. After running the installation command, your package manager will download and install vue-i18n and its dependencies. You’ll see it reflected in your package.json file. Now that we’ve got the core library, the next step is to actually set it up and integrate it into your Vue application so it’s ready to serve translations. This involves creating a configuration file and making it available throughout your app. We’re going to dive into that right after this!

Configuring vue-i18n in Vue 3

Now that you’ve successfully installed the vue-i18n package, it’s time to configure it for your Vue 3 application. This is where the magic happens, folks! We need to tell vue-i18n where to find your translation files and how to use them. The standard practice is to create a dedicated file for your i18n setup, often named i18n.js or i18n.ts (if you’re using TypeScript), usually located in a src/ or src/locales/ directory. Let’s create this file. Inside src/ , create a new folder named locales . Inside locales , create a file named i18n.js . This file will be the heart of your internationalization setup. Here’s what you’ll typically put inside it:

import { createI18n } from 'vue-i18n';

// Import your translation files
import en from './en.json';
import es from './es.json';

// Create a new i18n instance
const i18n = createI18n({
  legacy: false, // We recommend disabling legacy mode for Vue 3
  locale: 'en', // Set the default locale
  messages: {
    en: en,
    es: es,
  },
});

export default i18n;

In this code snippet, we’re importing the createI18n function from vue-i18n . We’re also importing our translation files, which in this example are en.json and es.json . You’ll need to create these JSON files (we’ll cover that next!). The key part here is createI18n . We pass an object with several options. legacy: false is crucial for Vue 3; it disables the legacy API, which is not recommended for new projects. locale: 'en' sets the default language your app will use when it first loads. Finally, messages is an object where each key is a locale code (like 'en' or 'es' ), and its value is the corresponding translation object imported from your JSON files. After setting up this configuration file, the next critical step is to make this i18n instance available throughout your Vue application. This is usually done in your main application entry file, typically main.js or main.ts . You’ll need to import your newly created i18n instance and use it with your Vue app instance. We’re almost there, guys!

Creating Translation Files

Awesome, you’ve got vue-i18n installed and configured! Now, let’s talk about the actual translations – the heart and soul of internationalization. These are typically stored in JSON files, making them easy to manage and update. Remember those en.json and es.json files we referenced in our i18n.js configuration? It’s time to create them! We’ll place these files inside the src/locales/ directory alongside our i18n.js file. Let’s start with English ( en.json ):

{
  "greeting": "Hello, World!",
  "welcome": "Welcome to our app.",
  "change_language": "Change Language"
}

And now, for Spanish ( es.json ):

{
  "greeting": "¡Hola, Mundo!",
  "welcome": "Bienvenido a nuestra aplicación.",
  "change_language": "Cambiar Idioma"
}

As you can see, each JSON file represents a specific language. The keys in these JSON objects (e.g., "greeting" , "welcome" ) are the unique identifiers for your text strings. The values are the actual text that will be displayed to the user in that particular language. This structure makes it super easy to manage translations. When you want to add another language, say French, you’d simply create a fr.json file in the same directory with the same keys but with French translations. The power here lies in the key-value structure. Your Vue components will use these keys to fetch the correct translation based on the currently active locale. This approach keeps your code clean and your translations organized. So, remember to keep your keys consistent across all language files. If you have a key in en.json but forget to add it to es.json , your Spanish users might see the English text or an error, which is definitely not the user experience we’re aiming for! Now that we have our translation files ready, the final step is to integrate them into your main Vue application entry point.

Integrating i18n with Your Vue App

We’re in the home stretch, guys! You’ve installed vue-i18n , configured it, and created your translation files. The final piece of the puzzle is to tell your Vue application to use the i18n instance we’ve set up. This is typically done in your main entry file, which is usually src/main.js (or src/main.ts ). You need to import your i18n instance and then pass it to your Vue app instance. Let’s look at how you’d modify your main.js file:

import { createApp } from 'vue';
import App from './App.vue';
import i18n from './locales/i18n'; // Import the i18n instance

const app = createApp(App);

app.use(i18n); // Use the i18n plugin

app.mount('#app');

See how simple that is? We import createApp from vue , import your main App.vue component, and crucially, we import the i18n instance we created in our locales/i18n.js file. Then, before mounting your app, you call app.use(i18n) . This tells Vue to register the vue-i18n plugin globally. From this point onwards, your i18n instance is available throughout your entire Vue application. You can now use the translation functions provided by vue-i18n in your components. For example, you can use the $t() function to translate text. In your <template> section, you could do something like:

<template>
  <div>
    <h1>{{ $t('greeting') }}</h1>
    <p>{{ $t('welcome') }}</p>
    <button>{{ $t('change_language') }}</button>
  </div>
</template>

And in your script section, you can access translations using this.$t('key') in Options API or t('key') from useI18n in Composition API. So, to recap, we’ve covered installing vue-i18n using npm or yarn, configuring it by creating an i18n.js file and defining locales and messages, setting up your actual translation content in JSON files, and finally, integrating the i18n instance into your main Vue app entry point. You’ve successfully completed the install i18n vue 3 process! Now you’re all set to make your Vue 3 application speak multiple languages. Go forth and internationalize!