Browser locale management options.


  • type: object | boolean
  • default: { alwaysRedirect: false, fallbackLocale: '', redirectOn: 'root', useCookie: true, cookieCrossOrigin: false, cookieDomain: null, cookieKey: 'i18n_redirected', cookieSecure: false }

Enables browser language detection to automatically redirect visitors to their preferred locale as they visit your site for the first time.

See also Browser language detection for a guide.

Note that for better SEO it's recommended to set redirectOn to root.

Set to false to disable.

Supported properties:


  • type: boolean
  • default: false

Set to always redirect to the value stored in the cookie, not just on first visit.


  • type: string or null

If none of the locales match the browser's locale, use this one as a fallback.


  • type: string
  • default: root

Supported options:

  • all - detect browser locale on all paths.
  • root (recommended for improved SEO) - only detect the browser locale on the root path (/) of the site. Only effective when using strategy other than 'no_prefix'.
  • no prefix - a more permissive variant of root that will detect the browser locale on the root path (/) and also on paths that have no locale prefix (like /foo). Only effective when using strategy other than 'no_prefix'.


  • type: boolean
  • default: true

If enabled, a cookie is set once the user has been redirected to browser's preferred locale, to prevent subsequent redirects. Set to false to redirect every time.


  • type: string
  • default: 'i18n_redirected'

Cookie name.


  • type: string or null
  • default: null

Set to override the default domain of the cookie. Defaults to the host of the site.


  • type: boolean
  • default: false

When true, sets the flags SameSite=None; Secure on the cookie to allow cross-domain use of the cookie (required when app is embedded in an iframe).


  • type: boolean
  • default: false

Sets the Secure flag for the cookie.