Authentication & Authorization APIs

Auth0 is a developer-friendly identity platform that handles user sign-up, login, social login, and multi-factor authentication so you do not have to build auth from scratch.

GetOTP lets you add one-time password (OTP) verification to your app via SMS, email, or WhatsApp with a few API calls.

Micro User Service provides programmatic access to user management and authentication via REST API.

MojoAuth is a passwordless authentication platform that lets users log in via magic links or one-time codes instead of passwords.

SAWO Labs provides programmatic access to simplify login and improve user experience by integrating passwordless authentication in your app via REST API.

Stytch provides ready-to-use user authentication infrastructure including magic links, OAuth, OTPs, and session management.

Warrant is an authorization API that lets you define and enforce fine-grained access control rules — roles, permissions, and object-level access — without building your own authorization logic.