head to head
Auth0 vs Keycloak
Keycloak is the open source alternative to Auth0 — identity and access management platform. Here is the honest comparison.
Yes — Keycloak is a viable free replacement for Auth0. Keycloak is open source under Apache-2.0, written in Java, with 36,832 GitHub stars, 8,941 forks and 3,292 open issues; it was last pushed 10 hours ago. Auth0 costs from $35, while self-hosting Keycloak carries no licence fee — the trade is your operational time instead of a subscription. 2 other open source Auth0 alternatives are tracked here, led by Authentik at 25,600 stars. Keycloak ranks #1 of 3 tracked open source Auth0 alternatives by stars. The tracked set, by adoption: Authentik (25,600 stars), Logto (14,580 stars). Replacement criteria on this page: 4 reasons to move to Keycloak and 3 reasons to stay on Auth0.
choose Keycloak if
- Your Auth0 bill is growing with seats or usage
- You need your data in a format and server you control
- Your compliance posture requires auditing the code that touches sensitive data
- You have (or can rent) a server and basic Docker comfort
stick with Auth0 if
- You need the polished onboarding and support SLAs of a commercial vendor
- Your team has zero capacity to operate software, even self-hosted-simple
- You depend on a Auth0 integration ecosystem that the OSS alternatives have not replicated
Side by side
| Keycloak (open source) | Auth0 | |
|---|---|---|
| Price | Free (self-hosted) | $35-$240/month |
| License | Apache-2.0 | Proprietary |
| Source code | Public, auditable | Closed |
| Self-hosting | Yes — keycloak/keycloak | Cloud only |
| Data ownership | Your server, your format | Vendor's cloud |
| Community | ★ 37K · ⑂ 8.9K | — |
| Built with | Java | — |
Why people look for a Auth0 alternative
About Keycloak
Keycloak is an open source identity and access management server, written in Java and licensed under Apache 2.0, that adds authentication and access control to applications and services, and it is intended for teams and organisations that want to own their user store rather than rent one.
read the full Keycloak overview →
Other open source alternatives to Auth0
last updated nightly · ranking method: github stars, live-tracked
Frequently asked questions
Is Keycloak a good replacement for Auth0?
Keycloak is an open source alternative to Auth0 (Identity and access management platform). It is written in Java and licensed under Apache-2.0, with 36,832 GitHub stars.
Is Keycloak free compared to Auth0?
Yes. Keycloak is open source — there is no licence fee, and you can self-host it. Auth0 is typically a paid subscription, so the trade-off is licence cost against the operational work of running it yourself.
How do I migrate from Auth0 to Keycloak?
Migration effort depends on the data formats involved. Check Keycloak's documentation for import options, and compare the feature table above to confirm the capabilities you depend on are covered before switching.