You can change the locale and timezone on a per user or per registration basis. The registration values, if set, will override the user values.

These are available to you on the user or registration object to use in your application.

Within the FusionAuth UI, they are used as well. While the FusionAuth admin UI isn't translated, if you change your user's locale to, say, FR, you will see dates displayed in the French format (12/1/2021 for Jan 12).

You can't set a global locale or timezone, but you can, as I mentioned, set up a webhook to do so. You could also write your own script to add users using the API or client libraries and always set a user's locale and timezone using that script.

HTH.

There's no way to set the default timezone for all new users in the UI, but you could set up a webhook on user creation which would set a default timezone. Here's more about webhooks: https://fusionauth.io/docs/v1/tech/events-webhooks/

You'd want either the user create or the user bulk create events: https://fusionauth.io/docs/v1/tech/events-webhooks/events/#user-create

I don't believe there's a way to change the locale of the FusionAuth admin UI. You can change the report timezone under "Settings > System > Reports" but that only addresses a small part of your question.

This seems like a bug (or maybe a feature?) so I filed an issue: https://github.com/FusionAuth/fusionauth-issues/issues/1066