Open alternatives9
Open-source apps that replace Auth0 and Okta
Keycloak is a free server that handles user sign-in and access control, so apps don't have to store passwords or check logins themselves. It is aimed at developers and organizations that run their own applications and services.
ZITADEL is a login and access system that lets apps and companies manage who can sign in and what they can do. It is aimed at developers and IT teams who want to run their own identity service or use a hosted one.

SuperTokens is a self-hosted service that handles user sign-up, login and session management for apps. It is aimed at developers who want to add login to their own applications while keeping control of user data.

Logto is an open-source system that handles user sign-in and login security for websites and apps. It is aimed at developers and companies that need to add accounts, single sign-on, and access control to their products.
Hanko is a login and user account system that developers add to their websites and apps, supporting passkeys, passwords, email codes and single sign-on. It can be run on your own server or used as a hosted service.

Authgear is a login and sign-up system that websites and apps can use so their users can sign in securely with passwords, passkeys, codes or social accounts. It is aimed at developers building consumer-facing products who want to add authentication without building it themselves.
Janssen is a set of open-source tools for managing digital identity and controlling who can access applications and services. It is aimed at companies and organizations that run their own login and access systems.
Ory Kratos is a server that handles user login, sign-up, password recovery and profile management so that apps do not have to build these themselves. It is aimed at developers and companies who run their own apps and need user accounts.
Ory Polis is a self-hosted service that lets companies sign users into apps using their corporate single sign-on systems, and keeps user accounts synced with company directories. It is aimed at developers and IT teams who build or run enterprise logins.
What's missing
What people still miss here, and wish existed. Upvote what matters to you.
Before you build
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About this page
Replaces fully means it does the main job of these apps; Replaces partly means it covers some of it.
Licenses: every project here uses an open-source license (what each one means). Open core means some parts are paid or under another license.
GitHub stars are shown for reference. They measure popularity, not whether it replaces anything.
Verified means r/TrueOpenSource mods checked it: open-source license, maintained, and it really does the job.
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