Start with Identity
Comparison · CIAM

FusionAuth vs Keycloak

CapabilityFusionAuthKeycloak
Overall
3.8
4.2
Authentication
4.5
4.5
SSO & Federation
3.0
4.5
Authorization
3.0
4.0
Lifecycle & Provisioning
3.0
3.5
MFA & Passwordless
3.5
4.0
Governance & Audit
3.0
3.5
Developer Experience
4.5
3.5
Deployment Flexibility
4.5
5.0
Pricing Transparency
3.5
5.0
Support & Ecosystem
3.0
3.5

Scored 0–5 against a published rubric. Bold marks the higher score. Independent analysis, no vendor sponsorship.

The honest comparison

FusionAuth and Keycloak are the two names that dominate the self-hosted identity conversation, but they sit on opposite sides of the open-source line. Keycloak is a fully open-source IAM project (CNCF-adjacent, backed by Red Hat) with no license cost and deep configurability. FusionAuth is a commercial product with a free community edition, flat per-instance pricing, and a more curated developer and operations experience, plus a managed cloud if you would rather not self-host.

When FusionAuth wins

  • You want self-hosting without the operational sharp edges of running Keycloak
  • Flat, predictable licensing and a managed cloud fallback matter
  • First-class multi-tenancy for B2B SaaS is a core requirement
  • You value polished APIs, docs, and a faster path from zero to working login

When Keycloak wins

  • Zero license cost is a hard requirement and you have the ops capability to run it
  • You want a fully open-source platform you can fork, audit, and extend
  • Deep protocol configurability and a large community and plugin ecosystem matter
  • You are standardizing on Red Hat or a CNCF-aligned stack

Pricing

Keycloak is free and open source; your cost is the infrastructure and the engineering time to operate it. FusionAuth has a free community edition and flat per-instance paid editions, so cost is predictable and does not scale with active users.

Verdict

Choose Keycloak when zero license cost and full open-source control outweigh operational effort. Choose FusionAuth when you want self-hosted ownership with a more polished product, flat pricing, strong multi-tenancy, and a managed option. Both beat per-MAU SaaS economics at scale. Compare against the managed developer-first route in Okta vs Auth0, and see SuperTokens vs FusionAuth for another self-hostable angle.

Last updated 2026-06-19

Independent, community-driven analysis. No vendor sponsorship. Compiled from public research and community input and verified on a best-effort basis, so details may be incomplete or out of date. Scores are opinions, not advice. Trademarks belong to their owners; mention does not imply affiliation or endorsement. See the full disclaimer, or send corrections to [email protected].