Authentik vs Authelia vs Keycloak: Choosing the Right Self-Hosted Identity Provider in 2026

If you're self-hosting applications in 2026, you've probably hit the authentication wall. Every app wants its own login. Your users are drowning in passwords. And you're one data breach away from a very bad week.

The solution is an identity provider: a central system that handles authentication for all your apps. The open-source world offers three serious options: Keycloak, Authentik, and Authelia. Each takes a fundamentally different approach to solving the same problem.

Choosing the wrong one means either wrestling with enterprise complexity you don't need, or discovering critical limitations after you've already deployed.

The Three Approaches

Keycloak is the enterprise heavyweight. Created by Red Hat, it's been around since 2014 and has the battle scars to prove it. It does everything: OAuth 2.0, OIDC, SAML, LDAP federation, fine-grained permissions, social login, and identity brokering. If a Fortune 500 company needs it, Keycloak probably supports it.

The trade-off is complexity. Keycloak's admin console is intimidating. Configuration requires understanding concepts like realms, clients, and mappers. The learning curve is steep, and the resource footprint is significant. It's the kind of tool where you'll spend a weekend just getting it running properly.

Authentik is the modern middle ground. Written in Python, it launched in 2020 and has grown rapidly (nearly 20,000 GitHub stars). The defining feature is its "flow" system, which lets you build custom authentication journeys through a visual editor. Want passwordless login for some users and MFA for others? You can configure that without touching code.

Authentik supports the same protocols as Keycloak (OAuth 2.0, OIDC, SAML) but wraps them in a cleaner interface. It's opinionated in ways that make common tasks easier. The downside is that it requires PostgreSQL and Redis, which adds infrastructure overhead for smaller deployments.

Authelia is the lightweight specialist. Unlike the other two, Authelia isn't a full identity provider. It's a forward authentication service that sits behind your reverse proxy (Traefik, NGINX, or Caddy) and gates access to applications. Think of it as a bouncer that checks credentials before letting anyone through.

Authelia's container is under 20 megabytes and typically uses less than 30 MB of memory. Configuration lives in YAML files. If you're running a homelab and just want MFA in front of your services without the complexity of a full IdP, Authelia is purpose-built for that use case.

Feature Comparison

When to Choose Each

Choose Keycloak if:

• You need SAML for legacy enterprise apps
• You're integrating with Active Directory or complex LDAP setups
• You require fine-grained authorization policies
• Your organization has dedicated identity management staff

Choose Authentik if:

• You want a modern UI without enterprise complexity
• Custom authentication flows are important (conditional MFA, user enrollment)
• You're a small-to-medium business or growing team
• You need a balance between features and usability

Choose Authelia if:

• You're running a homelab or small self-hosted setup
• You primarily need MFA in front of existing apps
• Minimal resource usage is a priority
• You prefer configuration files over admin interfaces

The Deployment Reality

Here's what the comparison charts don't tell you: the real cost of these tools is operational, not financial.

Keycloak works, but it's a behemoth. Expect to spend time understanding its data model before you can do anything useful. Updates sometimes introduce breaking changes. It's the tool you choose when you need its capabilities and have the team to support it.

Authentik hits a sweet spot for many organizations. The flow system genuinely reduces complexity for common authentication scenarios. Recent versions moved Remote Access Control from paid to free, which expanded its appeal significantly. If you're self-hosting business applications and want proper SSO without the Keycloak learning curve, Authentik is increasingly the default recommendation.

Authelia excels when you don't need a full identity provider. If your apps already have their own user management and you just want a consistent authentication layer in front of them, Authelia does that job exceptionally well. It integrates seamlessly with Traefik's forward auth middleware.

Getting Started

All three options are available as Docker containers, making initial deployment straightforward. For managed hosting with automatic updates and backups, Elestio offers one-click deployment for Keycloak, Authentik, and Authelia, removing the infrastructure management overhead.

The choice ultimately depends on your scale and requirements. Homelabs and personal projects: start with Authelia. Growing teams and SMBs: evaluate Authentik. Enterprise deployments with complex requirements: Keycloak remains the safe choice.

Whatever you pick, having centralized authentication is worth the setup investment. Your future self, managing dozens of services without dozens of passwords, will thank you.

Thanks for reading.