FusionAuth vs Keycloak

A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
FeatureFusionAuthKeycloak
CategoryIdentity & SSOIdentity & SSO
LicenseApache-2.0Apache-2.0
LanguageDockerfileJava
Setup difficultyMediumHard
Min. RAM1,024 MB1,024 MB
Deploymentdocker, kubernetes, bare-metaldocker, kubernetes, bare-metal
GitHub stars★ 241★ 36,058
First released20182014
ReplacesAuth0, OktaOkta, Auth0, Microsoft Entra ID

Why pick each one

Choose FusionAuth if…

  • Released under the Apache-2.0 license
  • First-class Docker support for quick deployment
  • Kubernetes-ready with Helm charts available
  • Written in Dockerfile
FusionAuth details

Choose Keycloak if…

  • Mature and battle-tested
  • Strong enterprise feature set
Keycloak details

Frequently asked questions

Is FusionAuth or Keycloak better?

Neither is universally better. Keycloak has the larger community, while FusionAuth is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.

Are FusionAuth and Keycloak free and open-source?

Yes. FusionAuth is licensed under Apache-2.0 and Keycloak under Apache-2.0. Both can be self-hosted at no software cost.

Can I run FusionAuth and Keycloak with Docker?

FusionAuth: yes. Keycloak: yes.

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