authentik vs Auth0
authentik
authentik is an open-source identity provider focused on flexibility and versatility. It supports SAML, OAuth2, OpenID Connect, LDAP, SCIM, and RADIUS protocols. It provides a modern UI for user self-service, admin management, and can act as a full identity provider or authentication proxy.
Pros
- Fully open source with active development
- Modern, polished admin UI
- Supports all major identity protocols
- Easy Docker/Kubernetes deployment
- Flexible flow-based authentication engine
Cons
- Younger project than Keycloak
- Smaller community and ecosystem
- Enterprise features require paid license
- Limited enterprise support options
Pricing: Free (Open Source) / Enterprise from contact
Auth0
Auth0 is a developer-focused customer identity platform (CIAM) now owned by Okta but sold as a separate product. It provides drop-in login, social sign-in, passwordless authentication, and multi-factor auth for applications, with SDKs for nearly every major framework. Auth0 is especially popular with SaaS startups because of its generous free tier and developer experience: you can go from zero to a working login flow in minutes.
Pros
- Excellent developer experience and documentation
- Generous free tier covers most early-stage apps
- Extensive SDKs for every major framework
- Actions and Rules allow flexible custom logic
Cons
- Pricing gets expensive fast past the free tier
- Okta acquisition raised long-term pricing concerns
- B2B pricing tier jumps sharply for simple orgs support
- Admin UI can feel dense for non-developer users
Pricing: Free up to 25,000 MAUs; B2C paid from $35/mo; B2B paid from $150/mo