This documentation is for a legacy version of Next.js and Supabase. For the latest version, please visit the Next.js and Supabase V2 documentation

Translations

Learn how to easily translate your Next.js Supabase Makerkit SaaS into multiple languages with our guide. Optimize your app and reach a wider audience.

Most strings in the Makerkit template's application use i18next, a library to translate your application into multiple languages. Thanks to this library, we can store all the application's text in json files for each supported language.

For example, if you are serving your application in English and Spanish, you'd have the following files:

  • English translation files at /public/locales/en/{file}.json
  • Spanish translation files at /public/locales/es/{file}.json

There are valid reasons to use translation files, even if you are not planning on translating your application, such as:

  1. it's easier to search and replace text
  2. tidier render functions
  3. easy update path if you do decide to support a new language

Adding new languages

By default, Makerkit uses English for translating the website's text. All the files are stored in the files at /public/locales/en.

Adding a new language is very simple:

  1. Translation Files: First, we need to create a new folder, such as /public/locales/es, and then copy over the files from the English version and start translating files.
  2. Next.js i18n config: We need to also add a new language to the Next.js i18n configuration at src/i18n/i18next.settings.ts.

Simply add your new language's code to the locales array.

The configuration will look like the below:

app/i18n/i18next.settings.ts
const fallbackLng = process.env.DEFAULT_LOCALE ?? 'en';
const languages: string[] = [fallbackLng, 'es', 'fr', 'it'];

Setting the default Locale

To set the default locale, simply update the environment variable DEFAULT_LOCALE stored in .env.

So, open the .env file, and update the variable:

.env
DEFAULT_LOCALE=de

Translating Server Components strings

To translate the server components strings, you need to initialize i18n in your Server Component using the following function:

const i18n = await initializeServerI18n(getLanguageCookie());

You can find examples of how we do it in every layout file.

Translating Client Components strings

When translating client components, you need to ensure you:

  1. Import the i18nProvider component and set the language provided from the server component
  2. Use the Trans component from ~/core/ui/Trans. An eslint rule will ensure you do not import it from react-i18next

For example, here is the SiteLayout layout:

function SiteLayout(props: React.PropsWithChildren) {
const data = use(loadUserData());
return (
<I18nProvider lang={data.language}>
<AuthChangeListener accessToken={data.accessToken}>
<SiteHeaderSessionProvider data={data} />
{props.children}
<Footer />
</AuthChangeListener>
</I18nProvider>
);
}