Auth0 vs Lucia
Pricing
Auth0: Free up to 7k MAU, from $23/mo
Lucia: Free and open source, deprecated since March 2025
Description
Auth0: Enterprise-grade auth that handles every login method, from social login to SAML SSO
Lucia: Open-source TypeScript session library, deprecated in March 2025 and replaced by a single-file code example you copy into your app
Pros
- Supports every auth method: social, email, passwordless, SAML, LDAP
- 7,000 MAU free tier is solid for early-stage products
- Battle-tested at scale, used by thousands of companies
- The replacement is plain code: one session file you own, with no package to update
- Free, no MAU limits, and your auth data stays in your own database
- The author's Auth Book explains sessions, passwords and OAuth in depth
Cons
- Way more complex than you need if you just want Google login
- Pricing tiers jump steeply: you can go from free to $240/mo quickly
- Documentation is extensive but can be hard to navigate
- The npm package is deprecated: no fixes or security updates
- You build everything yourself: no pre-built login UI, no hosted dashboard
- Requires solid understanding of sessions, cookies, and auth security
Details
Auth0 is the auth provider you pick when your app needs enterprise features: SAML SSO, LDAP, MFA policies, organization management. It supports every login method that exists and has been battle-tested by companies from startups to Fortune 500s. It is now part of Okta.
For solo founders, Auth0 is often more than you need. If you just want social login and email/password, Clerk or Supabase Auth is simpler and faster to set up. Where Auth0 earns its complexity is when you need to sell to companies that require SSO, or when compliance demands specific auth flows. Start with something simpler and migrate to Auth0 when enterprise requirements show up.
Lucia was auth stripped down to its essentials: a TypeScript library for session management, with helpers for password hashing, OAuth and token generation. There was no hosted service and no per-user pricing, just code running in your app and storing sessions in your own database.
The author deprecated the npm package in March 2025. The Lucia site and repository now offer a complete single-file session implementation to copy into your project instead, along with the Auth Book as a guide to building auth yourself. That route still suits developers who want full control, but it means owning the security of that code. For auth done in an afternoon, Clerk or Firebase Auth handle it as a managed service, and SuperTokens is an open-source option you can self-host.
Auth0 verified
Lucia verified
