Free-tier customer identity platforms

SuperTokens

SuperTokens is an open source user authentication platform that provides session management, login flows, and account security features for web and mobile applications. It supports email/password auth...

ZITADEL is an identity infrastructure platform for authentication and authorization. It provides hosted login, API-first identity management, social login templates, passwordless authentication, multifactor authentication, passkeys, role-based access control, and multi-tenant organization support.

MojoAuth

MojoAuth is a passwordless authentication API that provides OTP, magic links, passkeys, social login, SSO, and MFA through RESTful endpoints and SDKs. The service supports email OTP, phone OTP, WhatsA...

PropelAuth

PropelAuth is an authentication platform for B2B products. It provides hosted and self-hosted options for multi-tenant authentication, organization management, role-based access control, enterprise SSO, SCIM, API key authentication, user impersonation, audit logs, and MCP server authentication.

Firebase Authentication

Firebase Authentication is a backend identity service for apps that need user sign-in across mobile, web, and other platforms. It provides SDKs and ready-made UI libraries for email and password accou...

Hexclave

Hexclave is an open-source platform for user authentication, payments, and product signals. It provides hosted and self-hosted options, with documentation, SDKs, and dashboard access for integrating identity, messaging, analytics, and related product infrastructure.

Auth0

Auth0 is an authentication and authorization platform for web, mobile, and AI agent applications. It provides hosted login flows, social and enterprise connections, passwordless authentication, multif...

Phase Two

Phase Two provides managed Keycloak hosting and enterprise Keycloak support. The hosted offering runs Keycloak on dedicated, independently provisioned clusters with multi-region availability, unlimite...

Logto

Logto is an authentication and authorization platform for developers. It implements OIDC and OAuth 2.1 and adds sign-in flows, multi-tenancy, enterprise SSO, RBAC, MFA, organizations, machine-to-machine authentication, and account APIs for SaaS and AI applications.

Frontegg

Frontegg is a customer identity and access management platform for SaaS applications. It provides authentication, authorization, multi-tenant user management, SSO, SCIM, MFA, admin portals, and analytics through a low-code platform and developer APIs.

Clerk

Clerk is an authentication and user management platform that helps teams add secure sign-up, sign-in, and account management flows to web and mobile applications. It provides prebuilt UI components, A...

Kinde

Kinde is a developer platform for authentication, billing, access management, feature flags, and user management in SaaS applications. It provides hosted auth flows, SDKs for multiple languages and fr...