Keycloak vs Authentik in 2026: An Honest Comparison

Why Replace Auth0 or Okta With Open Source

Managed identity platforms like Auth0 and Okta charge per monthly active user, and the cost climbs fast as your user base grows. For developers and small teams, that pricing model turns your own authentication into a recurring tax. The open-source answer is to run your own identity provider — and the two names that dominate that conversation are Keycloak and Authentik.

Both are free, self-hostable, and battle-tested enough to run in production. They differ sharply in philosophy, though: Keycloak is the mature enterprise workhorse, while Authentik is the younger, more configurable upstart. This comparison walks through the differences so you can pick the one that fits your team.

A Brief Introduction

Keycloak is an identity and access management server backed by Red Hat, first released in 2014. It is Apache-2.0, written in Java, and sits at roughly 36,600 GitHub stars. It supports OIDC, SAML, OAuth 2.0, and user federation out of the box, and it is the de facto standard for open-source SSO in enterprise environments.

• Full OIDC, SAML, and OAuth 2.0 support
• Red Hat backing with a commercial build
• Deep enterprise features: realms, clients, identity brokering
• Battle-tested across more than a decade

Authentik is a newer identity provider written in Python/Django, first released in 2019. It is MIT-licensed and sits at roughly 25,400 GitHub stars. Its differentiator is a flow-based configuration model and a clean, modern admin UI, plus first-class reverse-proxy integration.

• Flow-based, visual configuration
• Modern admin UI
• Strong reverse-proxy (Traefik, Nginx, Caddy) integration
• Single-container deployment

In-Depth Features Comparison

Core Auth Features

Self-Hosting and Deployment

Integration and Protocols

Both speak OIDC and SAML, but with different strengths. Keycloak is the safe choice when you must integrate with legacy SAML enterprise apps. Authentik is the smoother choice for self-hosted homelabs and modern stacks, because its proxy providers integrate cleanly with Traefik, Nginx, and Caddy.

Security

Both projects take security seriously, but their track records differ in length.

Performance and Resource Footprint

Keycloak runs on the JVM, which gives it predictable performance that scales horizontally, but a heavier baseline memory footprint. Authentik is a Python/Django application that feels lighter at idle but runs several processes — a server, a worker, and a Redis dependency — that each consume resources.

Data and Migration

Both store users in their own database and both can import users from Auth0 or Okta over OIDC. Keycloak's deeper edge is user federation: it can plug directly into LDAP or Active Directory, which matters when you are migrating an existing enterprise identity store rather than starting fresh. Authentik handles LDAP through outposts, but its enterprise directory integration is less battle-tested.

Learning Curve and Configuration

This is where the two philosophies diverge most. Keycloak is powerful but its concepts (realms, clients, identity providers, mappers) take time to internalize, and the UI does not help. Authentik's flow builder visualizes the login pipeline, which makes complex flows easier to configure for newcomers.

Pricing Comparison

Both projects are free to self-host, so the real comparison is support and the managed tiers around them.

For value, both beat Auth0 or Okta the moment your monthly active users push you into a meaningful per-user bill. The difference is that Keycloak's commercial path is Red Hat's enterprise subscription, while Authentik's is a SaaS/enterprise offering from the project itself. If you do not need commercial support, both cost nothing but your server.

Overall Pros and Cons

Keycloak — Advantages: the most mature open-source IAM, unmatched SAML support, Red Hat backing, and a decade of production history. Disadvantages: a heavy Java footprint, a dated admin UI, and a steeper learning curve.

Authentik — Advantages: a modern UI, a genuinely useful flow-based configuration model, easy single-container deployment, and strong reverse-proxy integration. Disadvantages: a smaller community, less enterprise SAML depth, and fewer battle-tested references at very large scale.

Conclusion

Keycloak is ideal for larger organizations, multi-tenant SaaS platforms, and anyone who needs deep, enterprise-grade SAML federation. If you are replacing Auth0 in a company that lives in the enterprise identity world, Keycloak is the safer default.

Authentik is perfect for small teams, self-hosters, and homelabs that want a modern UI and an approachable configuration model without giving up OIDC or self-hosting. If you are a small technical team standing up SSO for the first time, Authentik gets you there faster.

Final thoughts: pick Keycloak when SAML breadth and enterprise maturity are non-negotiable; pick Authentik when modern UX, easy deployment, and reverse-proxy friendliness matter more. Both are free, both are credible Auth0 replacements, and either one removes the per-user identity tax.

See the full open-source Auth0 alternatives or browse the auth and identity category and its self-hosted options.

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OpenElse Editorial — OpenElse is a curated directory of open-source and self-hostable alternatives to developer SaaS, from Notion and Auth0 to Firebase and GitHub Copilot.