33.8k
Keycloak
Open Source Identity and Access Management solution for modern applications and services, offering single sign-on, user federation, and multi-factor authentication.
Open source alternatives to Auth0
Auth0 is hosted identity: login, social, and APIs. Open-source options range from a full IAM suite to a single-app login library.
Keycloak and Zitadel replace the identity provider. Authelia sits in front of apps you already host. Lucia and OpenAuth are libraries, not hosted IdPs. This directory currently lists 8 mapped tools, led by Keycloak (33.8k GitHub stars).
Quick comparison
| # | Tool | Stars | Language | License |
|---|---|---|---|---|
| 1 | Keycloak Open Source Identity and Access Management solution for modern applications and services, offering single sign-on, user federation, and multi-factor authentication. | 33.8k | Java | Apache License 2.0 |
| 2 | Authelia Authelia is a Single Sign-On Multi-Factor Authentication portal for web apps, providing secure and streamlined access management. | 27.5k | Go | Apache License 2.0 |
| 3 | Zitadel ZITADEL is a modern identity infrastructure that simplifies authentication and authorization for developers, providing advanced features like multi-factor authentication and single sign-on. | 13.5k | Go | GNU Affero General Public License v3.0 |
| 4 | Lucia A user-friendly authentication library designed to be simple and clean for developers. | 10.5k | — | BSD Zero Clause License |
| 5 | OpenAuth OpenAuth is a universal, standards-based authentication provider designed to simplify secure authentication for applications. | 5.7k | TypeScript | MIT License |
| 6 | Authgear-server authgear-server is an open-source authentication server that serves as an alternative to Auth0 and Firebase Auth. It provides secure, flexible, and scalable user authentication and identity management for web and mobile applications. | 1.6k | Go | Apache License 2.0 |
| 7 | React Query Auth Easily add authentication to your React applications using React Query, providing a seamless integration for secure and efficient login flows. | 411 | TypeScript | MIT License |
| 8 | React-auth Simplify your authentication flow when working with React applications, enhancing security and user experience. | 50 | TypeScript | MIT License |
How these Auth0 alternatives differ
Star rank is useful for adoption, not for picking a job. Use the diffs below to match the slice of Auth0 you actually need.
All open-source alternatives to Auth0
27.5k
Authelia
Authelia is a Single Sign-On Multi-Factor Authentication portal for web apps, providing secure and streamlined access management.
13.5k
Zitadel
ZITADEL is a modern identity infrastructure that simplifies authentication and authorization for developers, providing advanced features like multi-factor authentication and single sign-on.
10.5k
Lucia
A user-friendly authentication library designed to be simple and clean for developers.
5.7k
OpenAuth
OpenAuth is a universal, standards-based authentication provider designed to simplify secure authentication for applications.
1.6k
Authgear-server
authgear-server is an open-source authentication server that serves as an alternative to Auth0 and Firebase Auth. It provides secure, flexible, and scalable user authentication and identity management for web and mobile applications.
411
React Query Auth
Easily add authentication to your React applications using React Query, providing a seamless integration for secure and efficient login flows.
50
React-auth
Simplify your authentication flow when working with React applications, enhancing security and user experience.
Frequently asked questions
What is the best open source alternative to Auth0?
Keycloak for a full identity server. Zitadel if you want a newer cloud-native IdP. Authelia if you only need SSO in front of self-hosted apps.
Can I self-host an alternative to Auth0?
Yes. Keycloak, Zitadel, Authelia, and Authgear can be self-hosted. Library options stay in your app process.
Are these Auth0 alternatives free?
Yes. The servers and libraries listed here are open source. Some also sell managed hosting.
Related alternatives
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