Zitadel Alternatives for Developers

Last updated: June 2026

The strongest Zitadel alternatives for developers are Keycloak (the most feature-complete open-source IdP, self-hosted or managed via Skycloak), Authentik, Ory, FusionAuth, SuperTokens, and the commercial SaaS options Auth0 and WorkOS. Pick on three axes: licensing model (open source vs commercial), deployment (self-host, SaaS, or both), and protocol depth (OIDC and OAuth 2.0 only, or full SAML and directory federation too). Keycloak leads when you want maximum protocol coverage and a huge ecosystem; Ory and SuperTokens win on API-first, composable architectures; Auth0 and WorkOS trade self-hosting for a hands-off managed experience.

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Zitadel is a solid platform. It’s a Go-based, open-source IAM with a clean API-first design, native multi-tenancy, and a SaaS cloud option. So why look around? Maybe you need broader protocol support, a bigger plugin ecosystem, a different deployment model, or just want to compare before you commit. Whatever the reason, this is a roundup, not a takedown. Each tool here is genuinely good at something. Below you’ll find a one-line summary, who it suits, its licensing and deployment model, and an honest strength and weakness for each.

If you specifically want a deep, head-to-head breakdown of two of these tools, we already wrote one: see Keycloak vs Zitadel. This post stays at the roundup level so it complements that comparison instead of repeating it.

At a Glance

• The best all-around Zitadel alternative is Keycloak: it’s Apache 2.0 open source, supports OIDC, OAuth 2.0, and SAML 2.0, and runs self-hosted or managed via Skycloak.
• Ory and SuperTokens fit API-first and composable stacks; FusionAuth and Authentik suit teams that want a single self-hostable product.
• For a fully hands-off SaaS, Auth0 covers broad consumer and enterprise auth, while WorkOS specializes in adding enterprise SSO and directory sync.
• Choose on three axes: license, deployment model, and protocol depth, not on brand familiarity.

Why Look for a Zitadel Alternative?

Most teams evaluate alternatives for a handful of practical reasons, not because anything is broken. Common triggers include needing full SAML 2.0 as both identity provider and service provider, wanting a larger third-party plugin ecosystem, preferring a self-contained product over composable services, or matching a specific runtime your platform team already supports. Zitadel does many things well, so the question is rarely “is it bad?” It’s usually “is it the best fit for this stack?”

In our experience helping teams pick an IAM platform, the deciding factor is almost never a single missing feature. It’s deployment philosophy. Some teams want one product they fully control and host themselves. Others want a managed SaaS so identity is somebody else’s pager. And a growing group wants composable, API-first building blocks they can wire into a custom flow. Naming which of those three camps you’re in narrows seven options down to two or three fast.

Here’s a quick gut check before reading further. Do you need SAML federation with legacy enterprise systems? Do you want to self-host, or never touch infrastructure? Is your architecture frontend-first or backend-heavy? Your answers point straight at the right shortlist.

The Zitadel Alternatives at a Glance

The seven alternatives below split cleanly by licensing and deployment, which is the fastest way to shortlist. Five are open source and self-hostable (Keycloak, Authentik, Ory, FusionAuth, SuperTokens), and two are commercial SaaS (Auth0, WorkOS). Keycloak and SuperTokens also offer managed hosting paths, so “self-host vs SaaS” isn’t always binary. Use this table to narrow the field, then read the short sections for the nuance.

Tool	Open source?	Deployment	Best for
Keycloak	Yes (Apache 2.0)	Self-host or managed (Skycloak)	Full-protocol IdP with the biggest ecosystem
Authentik	Yes (core open source)	Self-host (commercial support available)	Teams wanting one self-hostable product with a slick UI
Ory	Yes (Apache 2.0 components)	Self-host or Ory Network (cloud)	API-first, composable, cloud-native architectures
FusionAuth	Source-available, free community edition	Self-host or hosted	A single downloadable product with strong developer docs
SuperTokens	Yes (core open source)	Self-host or managed	Frontend-first apps wanting embedded login and session control
Auth0	No	SaaS	Hands-off managed auth with broad consumer and enterprise features
WorkOS	No	SaaS	Adding enterprise SSO, SCIM, and directory sync to an existing app

A quick note on the open-source labels. “Open source” and “source available” are not the same thing, and licensing details shift over time. Always confirm the current license on each project’s repository before you build on it. We’ve kept the descriptions here to durable, well-established facts.

1. Keycloak: The Open-Source Heavyweight

Keycloak is the most feature-complete open-source identity provider available, and it’s the strongest all-around Zitadel alternative for developers. Licensed under Apache 2.0 and backed by Red Hat, it supports OIDC, OAuth 2.0, and SAML 2.0 as both identity provider and service provider, plus LDAP and Active Directory federation, identity brokering, and fine-grained authorization. You can self-host it or run it managed.

What it is: A full open-source IAM server and IdP.
Who it’s for: Teams that want maximum protocol coverage, deep customization, and the largest open-source identity ecosystem.
License and deployment: Apache 2.0; self-host (free) or managed via Skycloak.

Keycloak 26.x runs on Quarkus, which replaced the old WildFly base. That means faster startup, lower memory, configuration through kc.sh and keycloak.conf, and optional GraalVM native images. (If you’ve read older tutorials referencing standalone.xml or /auth/ URL paths, those are out of date.) Its standout strength is the Service Provider Interface (SPI) model, which lets you extend nearly every part of the system: custom authenticators, user storage, token mappers, and event listeners.

The honest weakness is operational overhead. Running Keycloak in production means managing a JVM application, a database, clustering, backups, and upgrades. That’s the exact burden a managed platform removes. Skycloak runs Keycloak for you so you keep the open-source feature set without the on-call rotation. To go deeper on the platform itself, see What Is Keycloak: A Complete Guide.

2. Authentik: One Self-Hostable Product With a Polished UI

Authentik is an open-core identity provider that appeals to teams who want a single self-hostable product with a modern admin experience. It supports the core standards (OIDC, OAuth 2.0, SAML), offers a flexible flow-builder for authentication sequences, and has grown a loyal following in the homelab and self-hosting community before moving up-market into businesses.

What it is: A self-hostable IdP with a configurable flow engine.
Who it’s for: Teams that want to own their identity stack with one product and a friendly UI.
License and deployment: Core is open source; commercial support and enterprise features available. Self-hosted.

Authentik’s standout strength is its visual flow system. You can compose login, enrollment, and recovery sequences from reusable stages without writing custom code, which is genuinely pleasant for teams that don’t want to live in config files. The UI is clean and the documentation is approachable.

The trade-off is ecosystem size. Authentik’s community and third-party integration catalog, while active and growing, are smaller than Keycloak’s long-established ecosystem. If your shortlist depends on an exact niche integration or a deep enterprise feature, verify support before you commit. For most self-hosting teams, though, it’s a strong and increasingly popular choice.

3. Ory: API-First and Composable

Ory takes a different shape from the all-in-one platforms. Instead of one monolithic server, it offers focused open-source components: Kratos for identity and user management, Hydra as an OAuth 2.0 and OIDC provider, Keto for permissions, and Oathkeeper as an access proxy. This API-first, composable design fits cloud-native and microservices architectures well.

What it is: A set of composable, API-first identity and authorization services.
Who it’s for: Teams building custom flows on a cloud-native stack who want headless building blocks.
License and deployment: Apache 2.0 components; self-host or Ory Network (managed cloud).

Ory’s standout strength is exactly that composability. There’s no prescribed UI and no opinionated monolith. You bring your own frontend and assemble only the pieces you need, which is liberating for teams that want full control over the user experience and the data model. Hydra in particular is a well-regarded, certified OAuth 2.0 and OIDC server.

The flip side: composability means more assembly. You’re wiring several services together and building your own UI, so the time-to-first-login is longer than a drop-in product. Teams that just want a login page out of the box may find it more involved than Authentik or FusionAuth. The freedom is real, and so is the work.

4. FusionAuth: A Single Downloadable Product

FusionAuth is a developer-focused identity platform delivered as a single downloadable application with notably thorough documentation. It supports OIDC, OAuth 2.0, and SAML, includes a built-in user management UI, and is known for being quick to get running locally. A free community edition covers a lot of ground, with paid tiers for advanced features.

What it is: A complete, downloadable identity and user management product.
Who it’s for: Teams that want one self-hostable product with excellent docs and a fast local start.
License and deployment: Source available, free community edition; self-host or hosted.

FusionAuth’s standout strength is developer experience around getting started. The documentation is genuinely good, the local setup is fast, and the feature breadth (registration, MFA, theming, webhooks) is wide for a single product. Many teams appreciate that they can download it and have a working IdP the same afternoon.

The consideration here is licensing nuance. FusionAuth is source available rather than a permissive open-source license like Apache 2.0, and some features sit in paid tiers. That’s a perfectly reasonable model, but it’s a different commitment than fully open-source projects. If license terms matter to your procurement or compliance team, confirm the current terms directly. We mention this because it genuinely affects the decision. Worth noting, we’ve also written about Keycloak identity brokering with FusionAuth if you end up running both.

5. SuperTokens: Frontend-First Login and Sessions

SuperTokens is an open-source authentication platform aimed at developers who want embedded login UI and tight control over sessions. Rather than redirecting to a hosted login page, it provides components and SDKs you drop into your app, plus a focus on secure session management. It’s a natural fit for frontend-heavy applications.

What it is: Open-source auth with embeddable login and strong session handling.
Who it’s for: Frontend-first teams that want in-app login components and granular session control.
License and deployment: Core is open source; self-host or managed.

SuperTokens’ standout strength is the developer experience for the common cases: email and password, social login, passwordless, and session management with rotating refresh tokens. The embedded UI keeps users inside your app rather than bouncing to a separate login domain, which some product teams strongly prefer.

The honest limitation is enterprise protocol depth. SuperTokens centers on application login rather than acting as a full SAML identity provider with directory federation. If your roadmap includes SAML SSO for enterprise customers or LDAP and Active Directory integration, a full IdP like Keycloak covers more ground. For consumer and B2B app login, though, SuperTokens is clean and pleasant to build on.

6. Auth0: Hands-Off Managed SaaS

Auth0 is the established commercial SaaS in this lineup and the most natural pick when you want managed authentication with zero infrastructure to run. It’s a closed-source platform with broad consumer and enterprise features: social login, MFA, SAML and OIDC SSO, directory integration, and an extensive SDK catalog with mature documentation. It’s owned by Okta.

What it is: A fully managed, commercial authentication and identity SaaS.
Who it’s for: Teams that want auth handled entirely by a vendor and don’t want to self-host.
License and deployment: Commercial, closed source; SaaS only.

Auth0’s standout strength is maturity and breadth. The platform is polished, the docs are deep, and the feature set covers most consumer and enterprise scenarios out of the box. For teams that value speed and a hands-off experience over self-hosting and source access, it’s a dependable choice.

The trade-offs are the usual SaaS ones: no self-hosting, your user data lives on the vendor’s infrastructure, and proprietary extensions (like custom logic hooks) can create lock-in if you ever migrate. The teams that outgrow a closed SaaS rarely do so over features. They do so over control and portability, which is precisely why a standards-based, open-source platform is the common landing spot for migrations. If you’re weighing this path, see our roundup of Auth0 alternatives, open source and managed.

7. WorkOS: Enterprise SSO as an Add-On

WorkOS is a commercial SaaS focused on making enterprise features easy to add to an application. It specializes in SSO (SAML and OIDC), directory sync via SCIM, and audit logs, and it also offers AuthKit for primary user authentication. It’s a common pick for SaaS companies that need to satisfy enterprise buyers, whether they already run their own login or want WorkOS to handle that too.

What it is: A commercial SaaS for enterprise SSO, SCIM, and directory sync.
Who it’s for: Product teams adding enterprise readiness on top of existing app auth.
License and deployment: Commercial, closed source; SaaS only.

WorkOS’ standout strength is that it does one job cleanly. SSO connections and directory sync are first-class, the integration work is well documented, and you don’t have to build SAML and SCIM plumbing yourself. For B2B SaaS teams chasing their first enterprise deals, that focus is genuinely valuable.

The thing to understand is where WorkOS started: its core strength is enterprise SSO and directory sync layered onto an app that already has its own login. WorkOS has since added AuthKit, a user-management and authentication product (email and password, social login, MFA) that’s free up to a generous user count, so it can also serve as your primary auth layer. Even so, many teams adopt WorkOS specifically for the enterprise SSO and provisioning piece on top of an existing login. If you’d rather have one open-source platform that covers both everyday login and enterprise SSO natively, a full IdP like Keycloak does both.

How to Choose the Right Zitadel Alternative

The right choice falls out of three questions, not a feature checklist. First, what’s your licensing preference: fully open source, source available, or commercial SaaS? Second, what’s your deployment model: self-host, managed, or hands-off SaaS? Third, how deep is your protocol need: app login only, or full SAML and directory federation too? Answer those three and your shortlist usually collapses to two options.

Here’s the practical mapping we use.

You want maximum protocol coverage and ecosystem

Go with Keycloak. It’s the broadest open-source IdP, covers OIDC, OAuth 2.0, and SAML 2.0, federates with LDAP and Active Directory, and has the largest plugin ecosystem. Self-host it if you have the DevOps capacity, or run it managed via Skycloak to skip the operational load.

You want one self-hostable product with a friendly UI

Look at Authentik or FusionAuth. Both give you a single product you control, with good admin experiences. Authentik’s flow builder is a highlight; FusionAuth’s documentation and fast local start are its calling cards. Confirm licensing terms for FusionAuth before you commit.

You’re building composable, API-first, or frontend-first apps

Choose Ory for headless, composable building blocks on a cloud-native stack, or SuperTokens for embedded in-app login and session control. Both trade out-of-the-box completeness for flexibility.

You never want to touch infrastructure

Pick Auth0 for broad managed auth, or WorkOS if you only need to bolt enterprise SSO and SCIM onto an app you already have. Both are SaaS-only, so you’re trading self-hosting and source access for convenience.

Frequently Asked Questions

What is the best open-source alternative to Zitadel?

Keycloak is the best open-source alternative to Zitadel for most teams. It’s licensed under Apache 2.0, supports OIDC, OAuth 2.0, and full SAML 2.0 as both IdP and SP, federates with LDAP and Active Directory, and has the largest open-source identity ecosystem. You can self-host it for free or run it managed via Skycloak. Authentik and Ory are strong open-source options too, depending on whether you want one product or composable services.

Is Zitadel open source?

Yes, Zitadel is open source and self-hostable. Note that its license changed with the v3 release in 2025: the main repository moved from Apache 2.0 to AGPL 3.0 (with some Apache 2.0 and MIT carve-outs for SDKs and selected directories), and a commercial license is available if AGPL terms don’t fit. It also offers Zitadel Cloud, a managed SaaS version. So when comparing alternatives, you’re not necessarily moving away from open source. Keycloak, Ory, and SuperTokens are Apache 2.0 open source, Authentik’s core is open source (MIT) under an open-core model, FusionAuth is source available, and Auth0 and WorkOS are commercial closed-source SaaS. Confirm each project’s current license on its repository before building on it.

Which Zitadel alternative supports SAML and LDAP?

Keycloak supports both SAML 2.0 (as identity provider and service provider) and LDAP and Active Directory federation natively, making it the most complete option for enterprise directory integration. Authentik, FusionAuth, and Ory’s Hydra cover SAML and OIDC to varying degrees, and the commercial options Auth0 and WorkOS offer SAML SSO and directory sync. SuperTokens focuses on app login rather than full SAML federation, so it’s a weaker fit if directory integration is a hard requirement.

Can I migrate from Zitadel to Keycloak?

Yes. Because both Zitadel and Keycloak speak standard OIDC, OAuth 2.0, and SAML, your application integration code largely transfers. The main migration work is moving user records and reconfiguring clients, identity providers, and flows in Keycloak. Both platforms expose APIs to script the export and import. Running Keycloak managed via Skycloak removes the infrastructure setup so you can focus on data migration rather than provisioning a cluster.

What’s the difference between a full IdP and a composable auth platform?

A full identity provider like Keycloak or Authentik gives you a complete, ready-to-run server with an admin UI, hosted login, federation, and protocol support out of the box. A composable platform like Ory hands you focused API-first services that you assemble and pair with your own UI. Full IdPs get you to a working login faster; composable platforms give you more control over the user experience and data model in exchange for more assembly.

Summary

Zitadel is a capable, modern, open-source IAM, and looking at alternatives is just good engineering diligence. The decision comes down to three axes: licensing model, deployment model, and protocol depth. Keycloak is the strongest all-around alternative thanks to its full protocol coverage and ecosystem, with self-hosted and managed paths. Authentik and FusionAuth suit teams wanting one self-hostable product. Ory and SuperTokens fit composable and frontend-first stacks. Auth0 and WorkOS are the hands-off commercial picks, with WorkOS focused specifically on enterprise SSO.

Name your camp, self-host, managed, or composable, and the shortlist writes itself. Then validate licensing terms and protocol support against your real requirements before you build. For a focused two-tool deep dive, our Keycloak vs Zitadel comparison goes further on architecture, multi-tenancy, and extensibility.

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Want the full open-source feature set of Keycloak without running the cluster yourself? Skycloak provides fully managed Keycloak hosting: OIDC, OAuth 2.0, and SAML support, with monitoring, backups, and upgrades handled for you. Explore managed Keycloak hosting to get started.