Descope

Frontegg

Frontegg is a customer identity and access management (CIAM) platform that secures the entry points into SaaS applications, describing itself as "the identity layer for every SaaS entry point." It provides a low-code approach to identity management so engineering teams can offload authentication, SSO, and multi-tenant user management instead of building it in-house. Beyond traditional CIAM, Frontegg also offers Agen.co, an enterprise-grade agentic layer that lets users interact with SaaS products safely through generative AI interfaces. The platform uses usage-based pricing tied to monthly active users, enterprise SSO/SCIM connections, and machine-to-machine token exchanges.

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.

Auth0

Auth0 is a developer-focused identity platform providing authentication, single sign-on, and authorization APIs/SDKs that applications integrate directly into their login flows. It offers a scalable and secure solution for managing user identities and access control, allowing developers to focus on building their applications without worrying about identity management.

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.