Auth0

logto

Logto is an open-source, developer-friendly identity solution designed for SaaS and AI applications. Built on modern standards like OpenID Connect and OAuth 2.1, it streamlines user management by offering robust out-of-the-box features. The platform enables development teams to quickly integrate secure login workflows, multi-factor authentication, and role-based access control without building complex identity systems from scratch.

Descope

Descope is a customer identity and access management (CIAM) platform that handles authentication and authorization for consumers, business customers, partners, and increasingly AI agents and MCP servers. It provides a no-code, drag-and-drop workflow builder for creating signup, login, MFA, and SSO flows without hand-rolling authentication logic. The platform supports a wide range of authentication methods including magic links, passkeys, social login, one-time passwords, SAML/OIDC SSO, and FIDO2, plus fine-grained authorization models like RBAC, ReBAC, and ABAC. Descope ships SDKs for major frontend and backend frameworks and offers identity orchestration that syncs with more than 50 third-party tools.

keycloak

Keycloak provides single sign‑on (SSO) and identity brokering for web, mobile, and API‑based applications. It supports standard protocols like OpenID Connect, OAuth 2.0, and SAML, allowing seamless integration with existing user stores. The platform includes an admin console, user self‑service, and fine‑grained authorization policies, all available under an Apache 2.0 license. It can be deployed on‑premises or used as a managed service, making it suitable for both startups and large enterprises.

FusionAuth

FusionAuth provides a complete customer identity and access management solution that developers can integrate quickly via APIs, SDKs, and webhooks. It handles authentication, authorization, and user lifecycle management while offering both cloud SaaS and self‑hosted deployments. The platform includes built‑in support for social logins, multi‑factor authentication, passwordless flows, and fine‑grained role‑based access control, making it suitable for everything from startups to large enterprises.

SuperTokens

SuperTokens is an open-source authentication solution that provides a comprehensive suite of features for secure user management. It offers session management, social/passwordless login, and multi-factor authentication, making it an ideal choice for developers and businesses looking to enhance their application's security. SuperTokens can be deployed either self-hosted or as a managed cloud service, providing flexibility and scalability.

Stytch

Stytch provides a developer‑focused authentication platform that lets you add passwordless login, single sign‑on, and robust fraud prevention to any application. Its APIs are designed for quick integration and scale with your user base. With built‑in support for magic links, biometrics, and multi‑factor authentication, Stytch helps you deliver secure, frictionless experiences while giving you tools to detect and block fraudulent activity in real time.