# 认证授权与用户管理 (Authentication, Authorization, and User Management)

> 托管登录、OAuth、SSO 和用户权限管理服务,免去自建账号体系。
> 共 28 个免费服务。数据来源:https://github.com/ripienaar/free-for-dev(MIT)。更新时间:2026-09-10

- [360username](https://360username.com/) — A free tool to search a username across 90+ social platforms to find matching profiles.
- [Aserto](https://www.aserto.com) — Fine-grained authorization as a service for applications and APIs. Free up to 1000 MAUs and 100 authorizer instances.
- [asgardeo.io](https://wso2.com/asgardeo) — Seamless Integration of SSO, MFA, passwordless auth and more. Includes SDKs for frontend and backend apps. Free up to 1000 MAUs and five identity providers.
- [Auth0](https://auth0.com/) — Hosted SSO. The free plan includes 25,000 MAUs, unlimited Social Connections, a custom domain, and more.
- [Authgear](https://www.authgear.com) — Bring Passwordless, OTPs, 2FA, SSO to your apps in minutes. All Front-end included. Free up to 5000 MAUs.
- [Authress](https://authress.io/) — Authentication login and access control, unlimited identity providers for any project. Facebook, Google, Twitter and more. The first 1000 API calls are free.
- [Authy](https://authy.com) — Two-factor authentication (2FA) on multiple devices, with backups. Drop-in replacement for Google Authenticator. Free for up to 100 successful authentications.
- [Cerbos Hub](https://www.cerbos.dev/product-cerbos-hub) — A complete authorization management system for authoring, testing, and deploying access policies. Fine-grained authorization and access control, free up to 100 monthly active principals.
- [Clerk](https://clerk.com) — User management, authentication, 2FA/MFA, prebuilt UI components for sign-in, sign-up, user profiles, and more. Free plan includes unlimited applications, 50,000 MRU limit per app, 3 dashboard seats, and more.
- [Cloud-IAM](https://www.cloud-iam.com/) — Keycloak Identity and Access Management as a Service. Free up to 100 users and one realm.
- [Descope](https://www.descope.com/) — Highly customizable AuthN flows, has both a no-code and API/SDK approach, Free 7,500 active users/month, 50 tenants (up to 5 SAML/SSO tenants).
- [duo.com](https://duo.com/) — Two-factor authentication (2FA) for website or app. Free for ten users, all authentication methods, unlimited, integrations, hardware tokens.
- [Kinde](https://kinde.com/) — Simple, robust authentication you can integrate with your product in minutes. Everything you need to get started with 7,500 free MAU.
- [logintc.com](https://www.logintc.com/) — Two-factor authentication (2FA) by push notifications, free for ten users, VPN, Websites, and SSH
- [Logto](https://logto.io/) — Develop, secure, and manage user identities of your product - for both authentication and authorization. Free for up to 5,000 MAUs with open-source self-hosted option available.
- [MojoAuth](https://mojoauth.com/) — MojoAuth makes it easy to implement Passwordless authentication on your web, mobile, or any application in minutes.
- [Okta](https://developer.okta.com/signup/) — User management, authentication and authorization. Free for up to 100 monthly active users.
- [Ory](https://ory.sh/) — AuthN/AuthZ/OAuth2.0/Zero Trust managed security platform. Forever free developer accounts with all security features, unlimited team members, 200 daily active users, and 25k/mo permission checks.
- [Permit.io](https://permit.io) — Auhtorization-as-a-service provider platform enabling RBAC, ABAC, and ReBAC for scalable microservices with real-time updates and a no-code policy UI. A 1000 Monthly Active User free tier.
- [Phase Two](https://phasetwo.io) — Keycloak Open Source Identity and Access Management. Free realm up to 1000 users, up to 10 SSO connections, leveraging Phase Two's Keycloak enhanced container which includes the [Organization](https://phasetwo.io/product/organizations/) extension.
- [PropelAuth](https://propelauth.com) — A Sell to companies of any size immediately with a few lines of code, free up to 200 users and 10k Transactional Emails (with a watermark branding: "Powered by PropelAuth").
- [Scalekit](https://scalekit.com) — Enterprise SSO (SAML, OIDC), SCIM provisioning, and social logins for B2B SaaS. Free tier includes 1 million MAU, 100 organizations, 1 SSO connection, and 1 SCIM connection.
- [Stack Auth](https://stack-auth.com) — Open-source authentication that doesn't suck. The most developer-friendly solution, getting you started in just five minutes. Self-hostable for free, or offers a managed SaaS version with 10k free Monthly Active Users.
- [Stytch](https://www.stytch.com/) — An all-in-one platform that provides APIs and SDKs for authentication and fraud prevention. The free plan includes 10,000 monthly active users, unlimited organizations, 5 SSO or SCIM connections, and 1,000 M2M tokens.
- [SuperTokens](https://supertokens.com/) — Open source user authentication that natively integrates into your app - enabling you to get started quickly while controlling the user and developer experience. Free for up to 5000 MAUs.
- [Unkey](https://www.unkey.com/) — Open-source API key management and rate-limiting platform. Free for up to 100,000 requests per month and 100 active API keys, with full access to key creation, revocation, and rate-limiting capabilities.
- [WorkOS](https://workos.com/) — Free user management and authentication for up to 1 Million MAUs. Support email + password, social auth, Magic Auth, MFA, and more.
- [ZITADEL Cloud](https://zitadel.com) — A turnkey user and access management that works for you and supports multi-tenant (B2B) use cases. Free for up to 25,000 authenticated requests, with all security features (no paywall for OTP, Passwordless, Policies, and so on).