--- source_url: "https://guptadeepak.com/ciam-compass/alternatives/open-source-ciam/" title: "Open Source CIAM: Best Self-Hosted Auth Alternatives (2026), CIAM Compass, CIAM Compass" mirrored_at: 2026-08-13T01:34:32.754Z host: guptadeepak.com cited_in_42a: true mirror_canonical: "https://index.42a.ai/guptadeepak.com/ciam-compass/alternatives/open-source-ciam/index" --- > **Original source:** https://guptadeepak.com/ciam-compass/alternatives/open-source-ciam/ [Home](https://guptadeepak.com/ciam-compass/)/[Alternatives](https://guptadeepak.com/ciam-compass/alternatives/)/Open source CIAM alternatives Self-hostingLast verified 2026-06-06 Open source CIAM is the answer to per-MAU cost, data sovereignty, and full control, but the real cost is operations, not licensing. This page is organized by job-to-be-done rather than one linear rank, because the choices split hard by operational profile, from the same capability matrix, with no vendor money. Ranked on: job-to-be-done, because OSS choices split by operational profile ## What open source CIAM actually costs - The license is free; the operations are not. The honest cost of self-hosted CIAM is deployment, scaling, patching, and on-call, not the per-MAU invoice you are escaping. - Sovereignty and control are the real wins. You decide where data lives, how it is configured, and when you upgrade, which is why regulated and privacy-driven teams choose this path. - Operational profile decides the pick. Kubernetes-native versus single-binary, heavy versus light admin, library versus platform: these split the field more than feature counts do. - Maturity varies widely. [Keycloak](https://guptadeepak.com/ciam-compass/vendors/keycloak/) is battle-tested at enterprise scale; the newer projects trade some of that for better ergonomics. Match the project's maturity to your risk tolerance. ## The open source picks, by job ### Keycloak de-facto OSS standard, max sovereigntyApache 2.0 Best for the job: De-facto OSS standard, maximum sovereignty You need a battle-tested, fully sovereign self-hosted CIAM. Keycloak wins when you want the most proven open source option and will staff its operations. Keycloak is the open source standard: Apache 2.0, broad protocol coverage, and a deployment base that runs at enterprise scale. It is the safest default when sovereignty and breadth matter more than ergonomics. The cost is operational weight, Keycloak is heavier to run and tune than the newer projects. Best for Teams that want the most proven OSS CIAM and have ops capacity to run it. Watch out for Heavier operations and a steeper admin learning curve than the modern entrants. [Read the Keycloak profile](https://guptadeepak.com/ciam-compass/vendors/keycloak/)[See Auth0 vs Keycloak](https://guptadeepak.com/ciam-compass/compare/auth0-vs-keycloak/) ### FusionAuth self-host without Keycloak's ops weightProprietary core with a free Community edition Best for the job: Self-host without Keycloak's operational weight You want self-hosting but not Keycloak's operational burden. [FusionAuth](https://guptadeepak.com/ciam-compass/vendors/fusionauth/) wins when you want self-hosted CIAM that is lighter to run than Keycloak. FusionAuth offers a free Community edition and a single-tenant deployment that is materially lighter to operate than Keycloak, with strong feature breadth. It is the pragmatic self-host pick for teams that want control without a platform team. The core is proprietary with a free tier, not a pure open source license, which is the trade for the ergonomics. Best for Teams that want self-hosted control with smaller operational overhead. Watch out for Core is proprietary (free Community edition), not OSI-licensed open source. [Read the FusionAuth profile](https://guptadeepak.com/ciam-compass/vendors/fusionauth/)[See Keycloak vs FusionAuth](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-fusionauth/) ### Zitadel strongest B2B Organizations modelApache 2.0 Best for the job: B2B Organizations and multi-tenancy You need real B2B Organizations in an open source platform. [Zitadel](https://guptadeepak.com/ciam-compass/vendors/zitadel/) wins when your self-hosted CIAM has to model B2B Organizations and tenants well. Zitadel is built around a first-class B2B Organizations and multi-tenancy data model, which most open source CIAM treats as an afterthought, under an Apache 2.0 license. For B2B SaaS that wants to self-host without giving up tenant modeling, it is the standout. It is younger than Keycloak, so weigh ecosystem maturity. Best for B2B SaaS that wants open source self-hosting with strong organization modeling. Watch out for Younger ecosystem than Keycloak; validate scale and connector coverage for your case. [Read the Zitadel profile](https://guptadeepak.com/ciam-compass/vendors/zitadel/)[See Keycloak vs Zitadel](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-zitadel/) ### Ory Kubernetes-native, Zanzibar-style FGAApache 2.0 Best for the job: Kubernetes-native deployments with fine-grained authorization You run Kubernetes and need native fine-grained authorization. [Ory](https://guptadeepak.com/ciam-compass/vendors/ory/) wins when you are Kubernetes-native and need Zanzibar-style fine-grained authz. Ory is a set of composable, API-first services (Kratos, Hydra, Keto) designed for Kubernetes, with Keto providing native Zanzibar-style relationship-based authorization. For platform teams that want identity as cloud-native infrastructure plus real FGA, nothing else on this list matches it. The composability is power and cost: you assemble and operate the pieces yourself. Best for Platform and infrastructure teams that want API-first identity and native FGA on Kubernetes. Watch out for Composable services mean you integrate and operate several components, not one product. [Read the Ory profile](https://guptadeepak.com/ciam-compass/vendors/ory/)[See Keycloak vs Ory](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-ory/) ### Authentik modern Keycloak replacement, nicer admin UIMIT Best for the job: Modern Keycloak replacement with a better admin experience You want Keycloak's coverage with a far better admin UI. [Authentik](https://guptadeepak.com/ciam-compass/vendors/authentik/) wins when you want Keycloak-class coverage with modern administration. Authentik delivers SSO, flows, and federation comparable to Keycloak's coverage under an MIT license, with a notably more modern admin UI and flow editor. It is the pick for teams that want Keycloak's role without Keycloak's administration pain. As a younger project, validate it at your scale and for your specific enterprise connectors. Best for Self-hosting teams that want Keycloak coverage with a cleaner operator experience. Watch out for Smaller deployment base than Keycloak; confirm enterprise-scale references for your needs. [Read the Authentik profile](https://guptadeepak.com/ciam-compass/vendors/authentik/)[See Keycloak vs Authentik](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-authentik/) ### SuperTokens auth as a library, pluggable recipesApache 2.0 Best for the job: Embed auth as a library rather than run a platform You want to embed auth in your app, not operate a separate platform. [SuperTokens](https://guptadeepak.com/ciam-compass/vendors/supertokens/) wins when you want auth as a library with pluggable recipes inside your stack. SuperTokens is auth delivered as a self-hostable library with composable recipes (email-password, passwordless, session management) you wire directly into your backend, under Apache 2.0. For teams that want to own auth code rather than operate a CIAM platform, it is the lightest-weight model here. The trade is that you build more of the surrounding surface yourself. Best for Developer teams that want to embed and own auth code rather than run a platform. Watch out for Library model means you build more of the admin and enterprise surface yourself. [Read the SuperTokens profile](https://guptadeepak.com/ciam-compass/vendors/supertokens/)[See SuperTokens vs Keycloak](https://guptadeepak.com/ciam-compass/compare/supertokens-vs-keycloak/) ## Job to pick Map your specific problem to the pick that removes it. If your job is What fixes it Maximum sovereignty, proven at scale [Keycloak](https://guptadeepak.com/ciam-compass/vendors/keycloak/) Self-host with lighter operations [FusionAuth](https://guptadeepak.com/ciam-compass/vendors/fusionauth/) Strong B2B Organizations modeling [Zitadel](https://guptadeepak.com/ciam-compass/vendors/zitadel/) Kubernetes-native plus fine-grained authz [Ory](https://guptadeepak.com/ciam-compass/vendors/ory/) Keycloak coverage, better admin UI [Authentik](https://guptadeepak.com/ciam-compass/vendors/authentik/) Embed auth as a library [SuperTokens](https://guptadeepak.com/ciam-compass/vendors/supertokens/) ## Comparison table Pulled from each vendor's capability matrix. Last verified 2026-06-06. Capability [Keycloak](https://guptadeepak.com/ciam-compass/vendors/keycloak/) [FusionAuth](https://guptadeepak.com/ciam-compass/vendors/fusionauth/) [Zitadel](https://guptadeepak.com/ciam-compass/vendors/zitadel/) [Ory](https://guptadeepak.com/ciam-compass/vendors/ory/) [Authentik](https://guptadeepak.com/ciam-compass/vendors/authentik/) [SuperTokens](https://guptadeepak.com/ciam-compass/vendors/supertokens/) Deployment self hosted, on prem, hybrid self hosted, cloud SaaS, on prem, hybrid cloud SaaS, self hosted self hosted, cloud SaaS, hybrid self hosted, on prem, hybrid self hosted, cloud SaaS Segment fit B2C, B2B SaaS, enterprise, public sector B2C, B2B SaaS, enterprise B2B SaaS, enterprise, public sector B2C, B2B SaaS, enterprise B2B SaaS, enterprise, public sector B2C, B2B SaaS, developer tools Pricing model free open source tiered MAU tiered MAU tiered MAU free open source tiered MAU Native passkeys ✓ Yes ✓ Yes ✓ Yes ✓ Yes ✓ Yes ✓ Yes B2B Orgs / Enterprise SSO Orgs ~ · SSO ✓ Orgs ✓ · SSO ✓ Orgs ✓ · SSO ✓ Orgs ~ · SSO ~ Orgs ✓ · SSO ✓ Orgs ✓ · SSO ✓ FedRAMP ✕ No ✕ No ✕ No ✕ No ✕ No ✕ No Fine-grained authz ✓ Yes ✓ Yes ✓ Yes ✓ Yes ✓ Yes ✓ Yes Free-tier ceiling Yes Yes 25k MAU 25k MAU Yes Yes ## How to choose - If sovereignty and proven scale matter most, [run Keycloak, the de-facto standard](https://guptadeepak.com/ciam-compass/vendors/keycloak/). - If you want self-hosting with less operational weight, [use FusionAuth or Authentik](https://guptadeepak.com/ciam-compass/vendors/fusionauth/). - If you need B2B Organizations or Kubernetes-native FGA, [use Zitadel for orgs or Ory for Kubernetes and FGA](https://guptadeepak.com/ciam-compass/vendors/zitadel/). - If you are unsure which operational profile fits, [answer six questions in the vendor selector](https://guptadeepak.com/ciam-compass/tools/vendor-selector/). ## Also worth knowing - [Logto](https://guptadeepak.com/ciam-compass/vendors/logto/) Aggressive pricing and a modern developer experience, MPL-2.0. [Head-to-head](https://guptadeepak.com/ciam-compass/compare/logto-vs-fusionauth/) - [Supabase Auth](https://guptadeepak.com/ciam-compass/vendors/supabase-auth/) Postgres-native auth with row-level security, bundled with the Supabase backend. - [WSO2 Identity Server](https://guptadeepak.com/ciam-compass/vendors/wso2-is/) Enterprise open source federation with deep standards coverage. [Head-to-head](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-wso2-is/) - [Hanko](https://guptadeepak.com/ciam-compass/vendors/hanko/) Passkey-first open source authentication for modern apps. - [BetterAuth](https://guptadeepak.com/ciam-compass/vendors/betterauth/) TypeScript-native auth library for the JS and TS ecosystem. - [Casdoor](https://guptadeepak.com/ciam-compass/vendors/casdoor/) Open source CIAM with Casbin-based authorization built in. [Head-to-head](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-casdoor/) - [Authelia](https://guptadeepak.com/ciam-compass/vendors/authelia/) Lightweight self-hosted SSO and 2FA portal for homelab and small deployments. [Head-to-head](https://guptadeepak.com/ciam-compass/compare/keycloak-vs-authelia/) - [Stack Auth](https://guptadeepak.com/ciam-compass/vendors/stack-auth/) Open source Clerk alternative tuned for Next.js. - [Tesseral](https://guptadeepak.com/ciam-compass/vendors/tesseral/) Open source B2B SaaS identity with a modern multi-tenant model. [See all open source vendors](https://guptadeepak.com/ciam-compass/vendors/) in the full vendor index, filtered by deployment model. ## FAQ What is the best open source alternative to Auth0? Keycloak is the de-facto open source default, with maximum sovereignty and the most proven deployment base. FusionAuth is the pick for lighter operations, Zitadel for the strongest B2B Organizations model, Ory for Kubernetes-native deployments with fine-grained authorization, Authentik as a modern Keycloak replacement with a nicer admin UI, and SuperTokens when you want auth as an embedded library. Is open source CIAM actually free? The license is free; the operations are not. Self-hosted CIAM removes the per-MAU invoice but you take on deployment, scaling, patching, and on-call. For most teams the real cost moves from a vendor bill to engineering headcount, which is why the honest comparison is operational profile, not licensing. Which open source CIAM is easiest to self-host? FusionAuth and Authentik are the lightest to operate: FusionAuth ships a single deployable with a free Community edition, and Authentik pairs Keycloak-class coverage with a far more modern admin UI. Keycloak is the most capable and proven but the heaviest to run and tune. Which open source CIAM is best for B2B SaaS? Zitadel, because it is built around a first-class B2B Organizations and multi-tenancy data model under an Apache 2.0 license, which most open source CIAM treats as an afterthought. Tesseral is a newer option also aimed squarely at B2B SaaS identity. ## Further reading from the blog Longer-form analysis on guptadeepak.com that pairs with this switching guide. - [Open Source CIAM: A Practical Guide for the Modern Enterprise](https://guptadeepak.com/open-source-ciam-a-practical-guide-for-the-modern-enterprise/) - [Why Open-Source CIAM Solutions Are Essential for Data Security and Privacy](https://guptadeepak.com/why-open-source-ciam-solutions-are-essential-for-data-security-and-privacy/) - [How Open Source Is Fueling the Future of Data Sovereignty and Digital Autonomy](https://guptadeepak.com/how-open-source-is-fueling-the-future-of-data-sovereignty-and-digital-autonomy/) ## Keep reading ## Editorial note This page ranks on one stated axis and nothing else. Every vendor is scored on the same matrix, every pick links to its internal profile, and we take no vendor money, no affiliate links, no paid placement. If you believe a claim is inaccurate or out of date, see the [disclaimer](https://guptadeepak.com/ciam-compass/disclaimer/) for how to reach the editorial team. Last verified 2026-06-06.