Keycloak vs authentik
Both are alternatives to Auth0. Here's how they stack up — verified facts, no spin.
Also searched as authentik vs Keycloak — same comparison, one verdict.
Keycloak and authentik are closely matched on ownership (90 vs 85) — this one comes down to pricing and to which trade-offs below you can live with.
Keycloak
TOP PICKThe mature, CNCF-backed open-source identity and access management server.
Keycloak is a full-featured IAM server originally built by Red Bull's security team and now a CNCF Incubating project. It supports OIDC, OAuth2, and SAML, social and enterprise identity brokering, fine-grained authorization, and a built-in admin console, and it's the most widely deployed self-hosted alternative to Auth0/Okta in production today.
authentik
A modern, self-hostable identity provider with a flexible visual flow builder.
authentik is a self-hosted identity provider built around a visual 'flow' system that lets you customize login, enrollment, and recovery steps without deep protocol expertise. It supports OIDC, SAML, LDAP, SCIM, and social login, and ships as a straightforward Docker Compose or Helm deployment aimed at teams who want Keycloak-class capability with a friendlier setup experience.
Side by side
10 points of comparison, every one read from a verified field. Green marks the side that wins a row outright. A dash means we do not hold that fact — never that it is zero.
| Keycloak | authentik | |
|---|---|---|
| Sovereignty ScoreOur transparent 0–100 composite for data ownership and exit cost. | 90 | 85 |
| Open source | Yes | Yes |
| Self-hostable | Yes | Yes |
| Local-first data | Yes | Yes |
| License | Apache-2.0 | MIT (core); authentik/enterprise/ subdirectory carries its own separate license for paid enterprise features |
| Pricing | Free / self-host (Docker image or standalone distribution); commercial support available via Red Hat build of Keycloak (RHBK) for enterprises that want a support contract. | Free / self-host for the core MIT-licensed product; a hosted 'authentik Security' cloud offering and an Enterprise tier (support SLA, extra features under the separate enterprise/ license) are available paid. |
| RAM to run it wellThe figure that actually matters, not the vendor's minimum. | 4 GB | 4 GB |
| Realistic running costWhat the box costs each month if you run it yourself. | $24–40/mo plus a database, against Okta or Auth0 per-user pricing that becomes brutal above the free tier | $15–25/mo, against Auth0 pricing that climbs steeply past the free tier |
| Setup timeHonest first-install estimate, not the marketing quickstart. | A day to stand up, a week to configure realms and flows correctly | Half a day for the server, longer per application you integrate |
| Ongoing maintenanceThe part nobody budgets for. | Moderate to high. It is enterprise software with an enterprise upgrade cadence and its own vocabulary. | Moderate, and the risk is concentrated: this is the front door to everything behind it. |
Keycloak is Macrostack's recommended Auth0 alternative, so it's our pick here.
Weighing both against staying on Auth0? Is Auth0 free? What it actually costs →
Keycloak
Strengths
- +Apache-2.0, fully open-source, no feature gating between a 'community' and 'enterprise' edition
- +Extremely mature — 10+ years in production at large scale, CNCF Incubating project with active governance
- +Broad protocol support (OIDC, SAML, OAuth2) and identity brokering to external IdPs out of the box
- +Large ecosystem of themes, extensions, and Kubernetes operators for production deployment
Trade-offs
- −Runs on the JVM — heavier resource footprint than lightweight Go-based alternatives, and the admin console/config model has a real learning curve
- −You own uptime, patching, and database backups for something security-critical — a genuine operational responsibility Auth0 absorbs for you
- −Theming the login UI to match a product's brand takes more custom work than Auth0's Universal Login customization
authentik
Strengths
- +Genuinely MIT-licensed for the core product — no AGPL copyleft concerns for embedding or forking
- +Visual flow builder makes multi-step login/enrollment/recovery customization far more approachable than editing raw protocol config
- +Good out-of-box support for LDAP and SCIM alongside OIDC/SAML, useful for bridging older enterprise directories
- +Active, fast-moving project with frequent releases
Trade-offs
- −The enterprise/ directory ships under authentik's own separate license, not MIT — some advanced features are gated behind the paid tier even when self-hosting the core
- −Younger and smaller community than Keycloak, so fewer third-party guides and Stack Overflow answers exist for edge cases
- −Flow builder flexibility means misconfiguration is possible; production hardening still requires real identity-ops knowledge
Which one fits you
The trade-offs above, turned into a decision. Find the line that describes your team.
Choose Keycloak
if a lower exit cost matters more to you than any single feature, and apache-2.0, fully open-source, no feature gating between a 'community' and 'enterprise' edition.
Choose authentik
if genuinely MIT-licensed for the core product — no AGPL copyleft concerns for embedding or forking.
Neither, yet
if both carry a real cost you should weigh first — runs on the JVM — heavier resource footprint than lightweight Go-based alternatives, and the admin console/config model has a real learning curve, and the enterprise/ directory ships under authentik's own separate license, not MIT — some advanced features are gated behind the paid tier even when self-hosting the core. If either of those is a dealbreaker for your team, the shortlist is wrong rather than the choice.
What it takes to run these yourself
Real requirements and honest running costs, not the vendor quickstart.
Self-hosting Keycloak
4 GB RAM · A day to stand up, a week to configure realms and flows correctly
$24–40/mo plus a database, against Okta or Auth0 per-user pricing that becomes brutal above the free tier
Self-hosting authentik
4 GB RAM · Half a day for the server, longer per application you integrate
$15–25/mo, against Auth0 pricing that climbs steeply past the free tier
Keycloak vs authentik — common questions
Is Keycloak a better fit than authentik for authentication & identity?
It depends on what you are optimising for, and the honest split is this: Keycloak scores 90 to authentik's 85 on data ownership and exit cost, so it is the safer choice if you care about being able to leave. authentik earns its place on a different axis — genuinely MIT-licensed for the core product — no AGPL copyleft concerns for embedding or forking. Neither is a wrong answer for every team; the table above is the actual comparison.
What happens if we want to switch later?
Keycloak keeps its data local or in open formats, so leaving is an export rather than a negotiation. authentik is still self-hostable, so the files stay on your server either way — but it is not local-first by design, so check what its export produces before you rely on it.
Can I self-host Keycloak or authentik?
Both can be self-hosted. The difference is what it costs you in time rather than whether it is possible — see the setup and maintenance rows above.
Are Keycloak and authentik both alternatives to Auth0?
Yes — both appear in our Auth0 comparison, which is why they are worth putting side by side. People usually arrive here already having decided to move off Auth0 and now choosing between the two replacements, which is a narrower and much easier question.
Related alternative guides
Facts verified 2026-07-14. Licenses and pricing change — spotted something out of date? That's a correction we want.