Authentication

285+ open-source auth tools — OAuth, SSO, passkeys, MFA, and session management. Alternatives to Auth0, Clerk, and Firebase Auth.

Unkey

The Developer Platform for Modern APIs

Authentication
apiapi-keysauthentication
Visit → 5206★
ALTCHA

ALTCHA offers cutting-edge spam and abuse protection for websites and apps, with privacy-friendly CAPTCHA alternatives designed for GDPR compliance.

Authentication
self-hostedcaptchaproof-of-work
Visit → 2106★ 1 AI recommendations
mCaptcha

Privacy-focused proof-of-work CAPTCHA system that silently protects websites without tracking users or requiring image solving. Drop-in replacement for reCAPTCHA.

Authentication
self-hostedcaptchaproof-of-work
Visit → 2425★
React Most Wanted

React starter kit with "Most Wanted" application features

Authentication
authenticationfacebook-loginfirebase
Visit → 2418★
FireZone

Replace your VPN with zero-trust access built on WireGuard. Fast, scalable network security with simple policies and identity provider integration.

Security Tools
self-hostedvpnwireguard
Visit → 8540★
Oauth2 Server

A spec compliant, secure by default PHP OAuth 2.0 Server

Authentication
oauthoauth2oauth2-server
Visit → 6646★
Oauth2 Proxy

A reverse proxy that provides authentication with Google, Azure, OpenID Connect and many more identi

Authentication
cloud-infrastructurehacktoberfestoauth2-proxy
Visit → 14062★ 2 AI recommendations
Tinyauth

The tiniest authentication and authorization server you have ever seen.

Authentication
2faauthenticationcaddy
Visit → 7137★ 1 AI recommendations
Dex

OpenID Connect (OIDC) identity and OAuth 2.0 provider with pluggable connectors

Authentication
hacktoberfestidentity-provideridp
Visit → 10679★
Kanidm

Kanidm: A simple, secure, and fast identity management platform

Authentication
authenticationiamidentity
Visit → 4703★
Gotrue

An JWT based API for managing users and issuing JWT tokens.

Authentication
authenticationjwtproduction
Visit → 4345★
Opencode Antigravity Auth

Enable Opencode to authenticate against Antigravity (Google's IDE) via OAuth so you can use Antigrav

Authentication
claudegeminigoogle
Visit → 9697★
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