Open source alternatives to Auth0

3 free tools that do the job of Auth0, most stars first. All are web apps you can run on your own server.

JobBackend and auth

3 alternatives

Sorted by most stars.

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Keycloak

Single sign-on and identity management for apps and services.

Also an alternative to Okta

Stars
37,703

Updated
5 days ago

License
Apache-2.0
Zitadel

Identity management with login, SSO and multi-tenancy, built for developers.

Web app

Stars
15,541

Updated
6 days ago

License
AGPL-3.0
Authgear

Login, SSO, MFA and passkeys as an open-source identity service.

Also an alternative to Okta

Stars
2,140

Updated
7 days ago

License
Apache-2.0

More alternatives in Backend and auth

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About these numbers. Stars, dates and licenses come from GitHub through ecosyste.ms, collected on 10 Nov 2026; they can lag GitHub by a few days. A project is listed only if it has 300 or more stars, was updated in the last 12 months and states a license. A listing is not an endorsement, and we have not tested these tools on Antideploy yet. Logos belong to their projects and companies and are shown only to say which is which.

Keycloak

Zitadel

Authgear