7 Best Auth0 Alternatives for Developers (2026)

The best Auth0 alternatives split into three groups: managed platforms, self-hosted open source, and source code you own outright. For fast setup, look at Clerk (strongest React and Next.js developer experience), Supabase Auth (bundled with Postgres), Firebase Auth (Google Cloud ecosystem), or WorkOS (enterprise SSO layered on an existing login system). For full control, Keycloak and SuperTokens are open source and self-hostable, and FastStaq ships a complete auth system as source code you buy once and keep.

An Auth0 alternative is any service or codebase that handles authentication instead of Auth0: sign-up, login, session management, and often multi-factor authentication and role-based access. Some are hosted APIs you subscribe to. Some are open source servers you run yourself. One on this list is source code you own after a single purchase.

You're probably comparing options because an Auth0 bill grew faster than expected, or because you're starting a new project and want more than the default choice on the table. Either reason gets you the same seven candidates below.

How we chose these Auth0 alternatives

We compared each option on four things: developer experience (how fast you can wire up sign-in), hosting model (managed, self-hosted, or source-owned), protocol coverage (OAuth, OIDC, SAML, SCIM), and pricing structure (subscription, usage-based, or one-time). We skipped tools that only handle a slice of the problem, like reverse-proxy forward-auth servers, since they don't compete directly with Auth0's scope.

I ran into the pricing tradeoff on a client project that had used Auth0 since launch. The integration worked well, and nobody wanted to replace a stable auth system. As monthly active users increased, though, identity became a growing line item in the budget even though the product’s login requirements had barely changed.

We moved the application to an auth system the team could host and control directly. The migration involved more than swapping SDK calls: we had to transfer users, preserve account links, replace session handling, test password-reset flows, and run both systems during the cutover. The lesson was simple. Managed auth can be the right choice when shipping speed matters most, but MAU pricing deserves attention before a growing user base turns a convenient dependency into an expensive migration project.

1. Clerk: best for React and Next.js teams

Clerk is a managed authentication platform built around drop-in UI components: SignIn, SignUp, UserButton, and OrganizationSwitcher, plus middleware for Next.js. It handles session lifecycle, social login, magic links, and multi-factor authentication, and adds multi-tenant organization management for B2B apps.

Best for developers shipping a React or Next.js product who don't want to build login screens from scratch.

Pricing note: Clerk uses usage-based pricing tied to monthly active users, with a free tier and paid tiers for higher volume plus per-connection enterprise SSO add-ons. The free-tier user limit has changed more than once in 2026, so treat any specific number you read as provisional.

Tradeoff: the components save real setup time, but you're renting your identity layer. If pricing changes again, moving a live user base off session tokens you don't control is genuine engineering work, not a config edit.

2. Supabase Auth: best if you want auth bundled with Postgres

Supabase Auth is the authentication layer of the Supabase platform, built on the open source GoTrue server and shipped alongside a hosted or self-hosted Postgres database, storage, and realtime subscriptions. It supports email/password, OAuth, magic links, and phone auth, and its biggest strength is how directly JWT claims flow into Postgres Row Level Security.

Best for teams already building on Supabase who want access rules to live close to the database instead of in a separate service.

Pricing note: Supabase offers a free tier plus paid per-project plans that scale with database size and usage. Confirm current tier limits on Supabase's pricing page, since they're adjusted periodically.

Tradeoff: the coupling to Postgres RLS is efficient for straightforward products, but once your authorization logic needs to span services outside Postgres or requires a richer role model, Supabase Auth starts to feel narrow.

3. Firebase Auth: best for the Google Cloud ecosystem

Firebase Auth is Google's authentication service, part of the broader Firebase platform built on the Firestore NoSQL database rather than a relational one. It covers email/password, phone auth, and the major social providers, with a setup process most developers can finish in an afternoon.

Best for teams already committed to Firebase or Google Cloud who want authentication to match the rest of their stack.

Pricing note: Firebase Auth follows Firebase's usage-based billing, with a free tier and pay-as-you-go pricing beyond it. Usage-based billing across a full Firebase project can be harder to predict than flat per-project pricing, so model your expected volume before committing.

Tradeoff: it's the fastest path if you're already on Firestore, but you inherit Firestore's document model instead of SQL, and customization options are more limited than Auth0, Keycloak, or SuperTokens.

4. Keycloak: best self-hosted option for enterprise identity

Keycloak is an open source, Java-based identity and access management server backed by Red Hat. It supports OpenID Connect, OAuth 2.0, SAML 2.0, and LDAP/Active Directory federation, plus fine-grained authorization with resource types, scopes, and policies, which is the most protocol-complete option on this list.

Best for teams that need SAML, directory federation, or complex authorization rules and have the infrastructure skills to run it.

Pricing note: Keycloak itself is free software; your cost is the infrastructure and the engineering time to run and tune it. Managed Keycloak hosting exists through third parties if you want the protocol coverage without the operations.

Tradeoff: Keycloak covers more identity protocols than anything else here, but it's a Java application with real memory overhead and a genuine learning curve. Budget for a DevOps person who enjoys reading admin console documentation, because someone will need to.

5. SuperTokens: best open source option you can still self-host

SuperTokens is an open source authentication library, not a standalone identity server. A backend SDK (Node.js, Python, or Go) exposes the auth APIs directly inside your application, a frontend SDK handles sessions and login UI, and a core service manages storage and rotating refresh tokens.

Best for teams that want an open source, self-hostable option but don't need Keycloak's full protocol stack.

Pricing note: the open source core is free to self-host; SuperTokens also offers a managed cloud version with paid tiers for teams that don't want to run the core themselves.

Tradeoff: because auth logic runs inside your own codebase instead of behind an external server, SuperTokens can't act as a standalone OIDC provider or SAML identity provider the way Keycloak can, and its role-based access control is more basic.

6. WorkOS: best for enterprise SSO on top of your own auth

WorkOS is a developer-focused platform built specifically for enterprise-readiness features: SAML and OIDC single sign-on, SCIM directory sync, audit logs, and admin portals, exposed through a clean API. It's not meant to replace your primary user auth; it's meant to sit alongside it once enterprise customers start asking for SSO.

Best for teams that already have a working auth system and need to check the enterprise procurement boxes without building SSO and SCIM themselves.

Pricing note: WorkOS's core user-management product (AuthKit) has a free tier for standard auth, while the enterprise building blocks (SSO, SCIM) are billed per connection. Since every enterprise customer typically needs both, per-connection costs scale with your highest-value accounts, so check WorkOS's current pricing page before you quote a customer.

Tradeoff: WorkOS does the enterprise slice well, but it's intentionally focused. It doesn't give you a full identity platform for your everyday users, so you're pairing it with something else regardless.

7. FastStaq: best if you'd rather own the auth code than rent it

FastStaq is a full-stack SaaS boilerplate that ships its own authentication system as part of the source code you receive, not as a hosted API you call. It includes email/password sessions, Google OAuth, magic links, TOTP two-factor authentication, trusted device tracking, API keys, and role-based access control with OWNER as the top role, all wired into a 76-model Prisma schema you're free to extend.

Best for developers who'd rather modify auth code directly than integrate against a vendor's API, particularly if a recurring per-user auth bill doesn't fit how you want to price your own product.

Pricing note: $299 one-time for lifetime access to the full source, with no per-seat or per-user fees. Full disclosure: I'm FastStaq's founder, so weigh that against the fact that it's the only option on this list with a fixed cost instead of a recurring one.

Tradeoff: you take on hosting, patching, and running the auth code yourself, the same tradeoff Keycloak and SuperTokens require, just delivered as an application codebase you install once instead of a server you deploy and keep updated.

Pro tip: whichever option you pick, write your app's auth calls behind a thin internal interface (a single auth.ts module, not calls to a vendor SDK scattered through your codebase). It won't save you from a migration, but it turns a rewrite into a refactor.

Auth0 alternatives compared

Note: Details for Clerk, Supabase Auth, Firebase Auth, Keycloak, SuperTokens, and WorkOS were verified in July 2026 and are general, publicly available positioning, not exact current pricing. Vendor pricing and free-tier limits change; check each provider's site for current terms before you budget. This table is reviewed quarterly.

How to choose the right Auth0 alternative

• You want the fastest React/Next.js setup and can accept a per-user bill: Clerk.

• You're already on Supabase or want auth wired directly to Postgres RLS: Supabase Auth.

• You're already deep in Google Cloud: Firebase Auth.

• You need SAML, LDAP federation, or fine-grained authorization and have DevOps capacity: Keycloak.

• You want open source and self-hosted without Keycloak's operational weight: SuperTokens.

• You have a working auth system and enterprise customers are asking for SSO/SCIM: WorkOS.

• You'd rather own and modify the auth code once than pay a recurring identity bill: FastStaq.

None of these is wrong. A managed platform is a legitimate choice if you'd rather pay for zero maintenance than spend engineering time on identity. Skip the self-hosted or source-owned options if you're pre-revenue and every hour matters more than every dollar; prioritize control once you have paying customers and predictable auth costs start to matter.

FAQ

What is the best free Auth0 alternative? Keycloak and SuperTokens are both open source and free to self-host, so your only cost is infrastructure and engineering time. Managed platforms like Clerk, Supabase Auth, Firebase Auth, and WorkOS also offer free tiers for smaller user counts, but costs scale as your user base grows.

Is there an open source Auth0 alternative? Yes. Keycloak, SuperTokens, and Supabase Auth are all open source and can be self-hosted, giving you full access to the code instead of depending on a vendor's hosted service. FastStaq's auth module is also part of the source code you receive, though FastStaq itself is a paid boilerplate rather than an open source project.

Can I self-host authentication instead of using a managed provider like Auth0? Yes. Keycloak, SuperTokens, and Supabase Auth all support self-hosting, and FastStaq ships auth as source code you deploy wherever you choose. Self-hosting trades a recurring vendor bill for the responsibility of running, patching, and scaling the auth system yourself.

Do these Auth0 alternatives support MFA and social login? Most do. Clerk, Supabase Auth, Firebase Auth, Keycloak, SuperTokens, and FastStaq all support social login, and multi-factor authentication is available in some form across all seven, though the specific methods (TOTP, WebAuthn, SMS) vary by vendor, so check each one's current auth methods if MFA type matters for your compliance needs.

What is the difference between a managed auth alternative and an own-your-auth boilerplate like FastStaq? A managed alternative like Clerk or WorkOS is a hosted API you integrate against and pay for on an ongoing basis, usually tied to user count. An own-your-auth boilerplate like FastStaq gives you the actual auth code in your repository for a one-time price, so you run it yourself and modify it directly instead of working within a vendor's SDK.

Where to go next

Auth0 alternatives split into managed platforms you rent, open source servers you self-host, and source code you own outright, and the right pick depends on how much control you want versus how much setup time you're willing to spend. If you're building on Next.js specifically, our Next.js authentication guide walks through wiring up sign-in end to end. If you're narrowing in on Clerk specifically, see our Auth0 vs Clerk comparison and Clerk alternatives roundup for a closer look.

If you want to see what an own-your-auth setup looks like before you decide, FastStaq ships OAuth, sessions, TOTP two-factor, and RBAC as part of its source code for $299 one-time, no per-seat fees.