{"slug":"best-self-hosted-oauth-and-openid-connect-server","title":"Best self-hosted OAuth and OpenID Connect server","question":"What are the best self-hosted OAuth and OpenID Connect servers in 2026?","category":"Auth","url":"https://modelsagree.com/best/best-self-hosted-oauth-and-openid-connect-server","updated":"2026-07-16","models":["ChatGPT","Claude","Gemini","Grok"],"consensus":"3 of 4 models rank Keycloak the top pick","disagreement":"Gemini picks authentik","combined":[{"rank":1,"product":"Keycloak","domain":"keycloak.org","score":19,"appearances":4,"modelRanks":{"ChatGPT":1,"Claude":1,"Gemini":2,"Grok":1},"reason":"The strongest all-round choice: mature OAuth 2.0/OIDC and SAML support, identity brokering, LDAP/AD federation, MFA/passkeys, fine-grained authorization, extensive customization, and a large operational knowledge base; best when broad standards coverage matters more than simplicity"},{"rank":2,"product":"ZITADEL","domain":"zitadel.com","score":14,"appearances":4,"modelRanks":{"ChatGPT":2,"Claude":2,"Gemini":3,"Grok":3},"reason":"A near-tie with Keycloak for cloud-native teams, combining polished OIDC/OAuth support, first-class organizations and multi-tenancy, passwordless authentication, strong APIs, auditability, and credible self-hosting; especially strong for B2B SaaS"},{"rank":3,"product":"authentik","domain":"goauthentik.io","score":13,"appearances":4,"modelRanks":{"ChatGPT":3,"Claude":5,"Gemini":1,"Grok":2},"reason":"Offers an extremely flexible visual flow-builder architecture, comprehensive out-of-the-box user management, a modern admin UI, and a built-in reverse proxy provider."},{"rank":4,"product":"Ory Hydra","domain":"ory.com","score":8,"appearances":4,"modelRanks":{"ChatGPT":5,"Claude":3,"Gemini":4,"Grok":4},"reason":"Best-in-class pure OAuth2/OIDC server — OpenID-certified, headless, stateless, horizontally scalable, and deliberately unopinionated about login/consent, which makes it ideal when you already own user management and want a hardened token engine; widely proven at very high request volumes."},{"rank":5,"product":"Duende IdentityServer","domain":null,"score":2,"appearances":1,"modelRanks":{"Claude":4},"reason":"The mature choice for .NET shops — OpenID-certified framework with deep protocol coverage (including token exchange, CIBA, DPoP tracking spec updates early), excellent documentation, and full control since it embeds in your own ASP.NET Core app rather than running as a black box. Assumption: ranked for practitioners in the .NET ecosystem; outside it, it doesn't apply."},{"rank":6,"product":"FusionAuth","domain":"fusionauth.io","score":2,"appearances":1,"modelRanks":{"ChatGPT":4},"reason":"A polished, developer-friendly self-hosted CIAM server with solid OAuth/OIDC implementation, convenient APIs and SDKs, tenant support, customizable login workflows, and simpler application integration than many enterprise IAM suites"},{"rank":7,"product":"Authelia","domain":"authelia.com","score":1,"appearances":1,"modelRanks":{"Gemini":5},"reason":"An incredibly lightweight, single-binary Go solution that integrates seamlessly with reverse proxies to secure applications using a simple YAML configuration."}],"perModel":{"ChatGPT":[{"rank":1,"product":"Keycloak","reason":"The strongest all-round choice: mature OAuth 2.0/OIDC and SAML support, identity brokering, LDAP/AD federation, MFA/passkeys, fine-grained authorization, extensive customization, and a large operational knowledge base; best when broad standards coverage matters more than simplicity","fix":"Its realm model, configuration surface, upgrades, and production clustering create substantial administrative complexity for small teams"},{"rank":2,"product":"ZITADEL","reason":"A near-tie with Keycloak for cloud-native teams, combining polished OIDC/OAuth support, first-class organizations and multi-tenancy, passwordless authentication, strong APIs, auditability, and credible self-hosting; especially strong for B2B SaaS","fix":"Event-sourced architecture and comparatively opinionated deployment make operating and troubleshooting it less familiar than conventional database-backed IAM"},{"rank":3,"product":"authentik","reason":"Excellent practitioner value for protecting self-hosted applications, with an approachable interface, flexible visual flows, OIDC/SAML, LDAP and proxy integrations, built-in outposts, and unusually good support for mixed modern and legacy apps","fix":"It is less proven for very large, protocol-demanding CIAM deployments, and its moving configuration and upgrade surface can require hands-on care"},{"rank":4,"product":"FusionAuth","reason":"A polished, developer-friendly self-hosted CIAM server with solid OAuth/OIDC implementation, convenient APIs and SDKs, tenant support, customizable login workflows, and simpler application integration than many enterprise IAM suites","fix":"Several capabilities organizations commonly want are commercial-edition features, making long-term cost and license boundaries a material consideration"},{"rank":5,"product":"Ory Hydra","reason":"A security-focused, OpenID-certified, API-first OAuth 2.0/OIDC server that excels when engineers want a scalable authorization server embedded in a custom identity architecture; near-tied with FusionAuth for protocol-centric platforms","fix":"It is deliberately headless and not a complete identity product, so login, consent, user management, recovery, and administration require additional Ory components or custom engineering"}],"Claude":[{"rank":1,"product":"Keycloak","reason":"The default answer for a reason — CNCF-graduated, battle-tested at enterprise scale, and covers nearly everything out of the box: OIDC/OAuth2/SAML, user federation (LDAP/AD), identity brokering, fine-grained authorization, admin console, and a huge extension ecosystem; Red Hat backing (as build of RHBK) gives it long-term credibility, and the newer Quarkus-based distribution cut its historical resource bloat considerably. Assumption: the typical practitioner wants a full IdP, not just a protocol server.","fix":"Operational heaviness remains real — JVM footprint, clustering/upgrade complexity, and a sprawling admin model make it overkill for small teams who need only OIDC login for a few apps."},{"rank":2,"product":"ZITADEL","reason":"The strongest modern challenger — Go-based single binary, multi-tenancy as a first-class concept, event-sourced audit trail, passkeys/WebAuthn done well, solid APIs/Terraform support, and Apache-2.0 licensed with an optional commercial cloud; it delivers most of Keycloak's IdP surface with far less operational drag. Near-tie with Keycloak for greenfield SaaS builders; Keycloak wins on ecosystem maturity and enterprise federation depth.","fix":"Requires CockroachDB/Postgres and its event-sourcing model makes some customizations and data migrations less straightforward; the extension/community ecosystem is much smaller than Keycloak's."},{"rank":3,"product":"Ory Hydra","reason":"Best-in-class pure OAuth2/OIDC server — OpenID-certified, headless, stateless, horizontally scalable, and deliberately unopinionated about login/consent, which makes it ideal when you already own user management and want a hardened token engine; widely proven at very high request volumes.","fix":"It is NOT an identity provider — you must build (or bolt on Ory Kratos for) login, consent, registration, and user storage yourself, so total effort is much higher than an all-in-one for typical deployments."},{"rank":4,"product":"Duende IdentityServer","reason":"The mature choice for .NET shops — OpenID-certified framework with deep protocol coverage (including token exchange, CIBA, DPoP tracking spec updates early), excellent documentation, and full control since it embeds in your own ASP.NET Core app rather than running as a black box. Assumption: ranked for practitioners in the .NET ecosystem; outside it, it doesn't apply.","fix":"Commercial license required beyond small-company/dev use, and it's a framework, not a product — no admin UI or user store; you build and maintain the hosting application yourself."},{"rank":5,"product":"authentik","reason":"The best self-hosted option for homelab-to-mid-size deployments — genuinely pleasant admin UI, OIDC/SAML/LDAP/SCIM plus proxy-based auth for apps with no native SSO, flexible flow/policy engine, and painless Docker deployment; it has largely displaced older options in the self-hosting community on usability alone.","fix":"Weaker fit for large-enterprise or high-assurance use — smaller security track record and team than Keycloak/Red Hat, and its flow engine's flexibility can hide misconfiguration foot-guns."}],"Gemini":[{"rank":1,"product":"authentik","reason":"Offers an extremely flexible visual flow-builder architecture, comprehensive out-of-the-box user management, a modern admin UI, and a built-in reverse proxy provider.","fix":"Its highly abstract staging and policy system introduces steep configuration complexity, making it overkill for basic authentication needs."},{"rank":2,"product":"Keycloak","reason":"Battle-tested enterprise reliability with unmatched protocol support (SAML, LDAP, Kerberos, OIDC) and a massive plug-in community.","fix":"Extremely heavy JVM-based resource footprint and steep learning curve, making it ill-suited for low-resource hosting or simple projects."},{"rank":3,"product":"ZITADEL","reason":"Built specifically for SaaS with first-class multi-tenancy (near-tie with Authentik, chosen over it if B2B multi-tenancy is the priority), event-sourced audit logs, and a modern Go-based API-first design.","fix":"Its rigid tenant-organization hierarchy adds unnecessary overhead and complexity for single-tenant or home lab deployments."},{"rank":4,"product":"Ory Hydra","reason":"A highly performant, secure, and lightweight Go-based engine that focuses strictly on standard-compliant OAuth2/OIDC token issuance.","fix":"It is strictly headless and provides no user database or authentication UI, requiring you to build or integrate these components yourself."},{"rank":5,"product":"Authelia","reason":"An incredibly lightweight, single-binary Go solution that integrates seamlessly with reverse proxies to secure applications using a simple YAML configuration.","fix":"Lacks advanced user registration workflows and comprehensive OIDC customization APIs, making it unsuitable for customer-facing applications."}],"Grok":[{"rank":1,"product":"Keycloak","reason":"Mature CNCF-backed enterprise standard with broadest protocol support (full OIDC, OAuth 2.0, SAML 2.0 IdP/SP, LDAP/AD federation, Kerberos), deep customization via SPIs, fine-grained authz (UMA), huge ecosystem/community, Red Hat support option, battle-tested at massive scale for typical self-hosted needs. Assumption: most practitioners value proven stability and integration breadth over minimalism.","fix":null},{"rank":2,"product":"authentik","reason":"Excellent balance of modern polished UI, flexible flows/stages, strong proxy outposts for legacy/non-SSO apps, full OIDC/SAML/LDAP/SCIM support, easy self-hosting with good performance — ideal for growing teams and heterogeneous internal tool estates.","fix":null},{"rank":3,"product":"ZITADEL","reason":"Modern Go-based, lightweight, API-first (gRPC/REST), native multi-tenancy/organizations, event-sourced auditing, strong passkeys/MFA, excellent for cloud-native/K8s and B2B SaaS practitioners needing scalable, developer-friendly self-hosted OIDC.","fix":null},{"rank":4,"product":"Ory Hydra","reason":"Highly composable, certified OAuth2/OIDC (Hydra), headless/modular design for custom UIs and developer-centric stacks, strong for API-heavy or microservices environments.","fix":null}]},"missedByModel":{"ChatGPT":[{"product":"Logto","reason":"polished developer experience and strong CIAM direction, but less mature operationally and less comprehensive for complex enterprise federation"},{"product":"Dex","reason":"excellent lightweight OIDC federation for Kubernetes-centric infrastructure, but too limited as a full user-facing identity and lifecycle-management server"}],"Claude":[{"product":"Authelia","reason":"excellent lightweight auth portal and now an OIDC provider, but its OIDC support is still maturing and it's scoped more to protecting reverse-proxied apps than serving as a general IdP"}],"Gemini":[{"product":"Dex","reason":"lacks built-in user management and functions strictly as a federated OIDC proxy to external upstream identity providers"},{"product":"FusionAuth","reason":"excellent performance but its proprietary core and license limitations on clustering restrict its utility compared to fully open alternatives"}],"Grok":[{"product":"FusionAuth","reason":"strong CIAM features and self-host but less dominant mentions/community traction vs top 3 in broad 2026 comparisons"}]}}