LoginRocket and the AuthRocket Core API are localized. The Configuration API and management portal are only available in English.

AuthRocket’s default email subjects and templates are also localized. Each localized version may be customized (or disabled) as appropriate for your app.

At the moment, English, Japanese, and Spanish are supported.

The default locale

Each Realm has a configurable default locale which is used by LoginRocket and outbound emails when no other locale is specified.


LoginRocket selects the active locale based on the user’s preference, the user’s browser, and then falls back to using the default locale. The experience is designed to be as seamless for the user as possible.

LoginRocket also updates the locale field on the User record, both for its own use and to make available to your app via JWT login tokens and the API.

Invitations of other users have no way of knowing the invited user’s preferred locale. In this case, the realm’s default locale will be used for those outbound emails.

AuthRocket API

AuthRocket’s Core API responds to the standard HTTP Accept-Language header. Validation errors (status 422) will be returned according to the current locale. If Accept-Language is missing or invalid, English is used.

When User.locale is present, JWTs generated by AuthRocket (via both the API and LoginRocket) will contain a locale claim depending on the selected scope(s).

Hint: Sending Accept-Language will not automatically set User.locale when creating or updating users. To set a user’s locale and localize any returned error messages, the desired locale will need to be sent for both User.locale and Accept-Language.