Phoenix Guide Best Authentication for Phoenix (2026)
Compare the best authentication solutions for Phoenix. We review phx.gen.auth, Guardian, and third-party providers with Elixir integration.
Phoenix has excellent built-in authentication generators and JWT libraries. We've evaluated authentication solutions that work well with Elixir's functional patterns.
Why This Matters
Phoenix's authentication generators provide secure defaults out of the box. Third-party providers add features like social login and MFA without complexity.
Key Considerations
phx.gen.auth
Built-in generator creates complete auth system. Email/password, sessions, password reset. Secure by default.
Guardian JWT
Guardian is the standard JWT library for Elixir. Works with any token issuer. Good for APIs.
Plug-Based Auth
Phoenix uses plugs for auth middleware. Easy to integrate any provider with custom plugs.
LiveView Auth
LiveView has built-in auth patterns. Sessions work across HTTP and WebSocket connections.
Ueberauth
Ueberauth provides OAuth strategies for social login. Many provider strategies available.
Our Recommendations
Auth0
Best Managed Good SupportAuth0 works with Phoenix via OIDC. Use Guardian to validate JWTs. 7,500 MAU free. Full-featured auth without managing users.
Use ueberauth_auth0 or validate JWTs with Guardian 
Clerk
Best DX Good SupportClerk provides modern auth with great DX. Validate JWTs with Guardian. 10,000 MAU free. Best frontend components.
Validate Clerk JWTs with Guardian 
Supabase Auth
Best Free Good SupportSupabase Auth works as JWT issuer. Validate with Guardian. 50,000 MAU free. Good value for Phoenix projects.
Validate Supabase JWTs with Guardian 
Keycloak
Best Self-Hosted Good SupportKeycloak for enterprise self-hosted auth. OIDC works with Guardian. SAML, LDAP support. Free and open source.
Configure OIDC with Guardian 
Firebase Authentication
Best Google Good SupportFirebase Auth works with Guardian JWT validation. Google ecosystem integration. Generous free tier.
Validate Firebase JWTs with Guardian Quick Comparison
| Service | TypeScript | Edge | Free Tier | Setup Time |
|---|---|---|---|---|
| Auth0 | none | — | 7,500 MAU | 30 min |
| Clerk | none | — | 10,000 MAU | 25 min |
| Supabase Auth | none | — | 50,000 MAU | 25 min |
| Keycloak | none | — | Unlimited (self-host) | 45 min |
| Firebase Authentication | none | — | 50,000 MAU | 30 min |
Quick Start
defmodule MyAppWeb.Guardian do
use Guardian, otp_app: :my_app
def subject_for_token(user, _claims) do
{:ok, to_string(user.id)}
end
def resource_from_claims(claims) do
user = MyApp.Accounts.get_user!(claims["sub"])
{:ok, user}
rescue
Ecto.NoResultsError -> {:error, :resource_not_found}
end
endCommon Integration Patterns
phx.gen.auth + Guardian
Built-in session auth for web, Guardian for API tokens.
Auth0 + LiveView
Auth0 for authentication, session tokens for LiveView.
Ueberauth + Social Login
Ueberauth strategies for Google, GitHub, Twitter, etc.