Best Self-Hosted SSO & Authentication Tools

Quick Picks

Use Case	Best Choice	Why
Homelab SSO	Authelia	Lightweight, fast setup, <30 MB RAM
Growing team	Authentik	Full IdP with user management, enrollment flows
Enterprise/Java shops	Keycloak	Industry standard, SAML + OIDC + LDAP, massive ecosystem
Cloud-native / API-first	Zitadel	Modern Go-based IdP, gRPC API, built for Kubernetes
Lightweight LDAP only	LLDAP	Minimal LDAP server if you just need directory services

Why Self-Host Authentication?

Every self-hosted app that needs login — Nextcloud, Gitea, Grafana, Portainer — creates another set of credentials to manage. SSO (Single Sign-On) solves this: one login, one session, access to everything. Self-hosting your identity provider means you control who gets access, how they authenticate, and where their credentials are stored.

Cloud SSO services like Okta ($2-15/user/month), Auth0 ($23+/month), and Google Workspace charge per-user fees that grow fast. Self-hosted SSO is free — you pay only for the server it runs on.

The Full Ranking

1. Authelia — Best for Homelabs

Authelia is a single Go binary that sits behind your reverse proxy and handles authentication for all your services. It supports TOTP, WebAuthn, and Duo for 2FA, and implements OIDC for apps that support it. Configuration is YAML-based — no web UI for admin, but the config is simple enough that you won’t miss one.

Pros:

• Tiny footprint — single container, <30 MB RAM idle
• 5-10 minute setup with Nginx Proxy Manager or Traefik
• YAML config is version-controllable and easy to reason about
• OIDC provider for apps that support OpenID Connect
• WebAuthn/FIDO2 support for passwordless authentication

Cons:

• No admin web UI — all config is YAML files
• No SAML support (OIDC only)
• No built-in user management UI — users defined in YAML or LDAP
• No enrollment flows or self-service password reset (without SMTP)

Best for: Solo homelabbers or small teams who want SSO without the overhead.

[Read our full guide: Self-Hosting Authelia]

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2. Authentik — Best for Growing Teams

Authentik is a full identity provider with a polished web UI, user management, enrollment flows, and application directory. It supports OIDC, SAML 2.0, LDAP (as both client and provider), SCIM, and proxy authentication. The enrollment flow system lets you build custom onboarding experiences — email verification, approval workflows, terms acceptance.

Pros:

• Modern web UI for administration and user self-service
• Enrollment flows (custom signup, approval workflows, MFA enrollment)
• OIDC + SAML 2.0 + LDAP + SCIM — broadest protocol support short of Keycloak
• Outpost system for distributed proxy authentication
• User impersonation for debugging
• Active development, growing community

Cons:

• Heavier than Authelia — requires PostgreSQL + Redis + server + worker (4 containers minimum)
• 150-200 MB RAM idle
• Python/Django backend is slower than Go alternatives for high-throughput scenarios
• Younger project than Keycloak (less enterprise documentation)

Best for: Teams of 5-50 who need user management, enrollment flows, and multi-protocol support.

[Read our full guide: Self-Hosting Authentik]

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3. Keycloak — Best for Enterprise

Keycloak (by Red Hat) is the industry-standard open-source identity and access management platform. It supports every authentication protocol (OIDC, SAML 2.0, LDAP, Kerberos), has the deepest feature set, and is backed by Red Hat’s enterprise support ecosystem. If you’re integrating with enterprise applications that expect SAML, Keycloak is the safest bet.

Pros:

• Industry standard — the most widely deployed open-source IdP
• Every protocol: OIDC, SAML 2.0, LDAP, Kerberos, OAuth 2.0
• Fine-grained authorization services
• User federation (connect to existing LDAP/AD directories)
• Themes and branding customization
• Red Hat backing and enterprise support available
• Extensive documentation and community resources

Cons:

• Java-based — heavier resource footprint (500 MB+ RAM)
• Admin console has a learning curve
• Configuration complexity matches feature depth
• Can feel over-engineered for simple homelab use cases

Best for: Enterprises, organizations with SAML requirements, shops already running Java infrastructure.

[Read our full guide: Self-Hosting Keycloak]

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4. Zitadel — Best Cloud-Native Option

Zitadel is a modern identity management platform written in Go with a gRPC-first API design. It combines authentication, authorization, and user management into a single binary. The architecture is designed for Kubernetes and cloud-native deployments, with built-in multi-tenancy and organization support.

Pros:

• Single binary (Go) — lighter than Keycloak
• gRPC + REST API — excellent for infrastructure-as-code workflows
• Built-in multi-tenancy and organization management
• Passwordless authentication (WebAuthn/FIDO2) as a first-class feature
• Actions system (custom logic on auth events, like Authentik’s flows)
• Strong Kubernetes support

Cons:

• Younger project — smaller community than Keycloak or Authelia
• Requires CockroachDB or PostgreSQL
• Less reverse proxy integration documentation than Authelia
• Some features are still maturing

Best for: Teams building cloud-native infrastructure who want a modern IdP with API-first design.

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5. LLDAP — Best Lightweight LDAP

LLDAP (Light LDAP) isn’t an SSO solution — it’s a minimal LDAP server. If your apps support LDAP authentication and you just need a lightweight user directory without the full weight of Keycloak or Authentik, LLDAP fills that niche. Written in Rust, it uses ~10 MB RAM and has a simple web UI for user/group management.

Pros:

• Extremely lightweight (~10 MB RAM, Rust binary)
• Simple web UI for user and group management
• Standard LDAP protocol — works with any LDAP-compatible application
• Easy to set up as a backend for Authelia or other SSO tools

Cons:

• LDAP only — no OIDC, no SAML, no SSO
• Not a standalone SSO solution
• Limited to user directory management
• Small community

Best for: Homelabs that need a shared user directory for LDAP-compatible apps, or as a backend for Authelia’s LDAP authentication.

Full Comparison Table

Feature	Authelia	Authentik	Keycloak	Zitadel	LLDAP
Language	Go	Python	Java	Go	Rust
OIDC	Provider	Provider	Provider	Provider	No
SAML 2.0	No	Yes	Yes	Yes	No
LDAP	Client only	Provider + Client	Provider + Client	No	Provider
Proxy auth	Yes (primary mode)	Yes (Outposts)	Yes (adapter)	No	No
Admin web UI	No (YAML config)	Yes	Yes	Yes	Yes (basic)
2FA methods	TOTP, WebAuthn, Duo	TOTP, WebAuthn, SMS, Email	TOTP, WebAuthn	TOTP, WebAuthn, U2F	No
User self-service	Limited	Full (flows)	Yes	Yes	No
Min containers	1	4	1-2	1-2	1
Idle RAM	~30 MB	~200 MB	~500 MB	~100 MB	~10 MB
GitHub stars	26k+	20k+	24k+	10k+	5k+
Maturity	2019+	2020+	2014+	2020+	2022+

Decision Framework

“I just want SSO for my 5 self-hosted apps and I’m the only user” → Authelia. 5-minute setup, minimal resources, covers reverse proxy auth and OIDC.

“I have a small team and need user management with enrollment” → Authentik. Web UI for managing users, SAML support for apps that need it, enrollment flows for onboarding.

“I’m running enterprise apps that require SAML and LDAP federation” → Keycloak. Industry standard, broadest protocol support, enterprise documentation.

“I’m building on Kubernetes and want API-first identity management” → Zitadel. Modern architecture, gRPC API, built for cloud-native.

“I just need a lightweight user directory for LDAP-compatible apps” → LLDAP. Minimal LDAP server, 10 MB RAM, simple web UI.

Related

• Self-Hosting Authelia
• Self-Hosting Authentik
• Self-Hosting Keycloak
• Authelia vs Authentik
• Authelia vs Keycloak
• Authentik vs Keycloak
• Zitadel vs Keycloak
• Security Basics for Self-Hosting
• Reverse Proxy Setup
• Docker Compose Basics