Auth0 is an identity and authentication platform providing universal authentication and authorization services — handling secure login, identity management, and single sign-on (SSO) so developers don't have to build authentication from scratch, reducing weeks of security-critical development to hours of configuration.

What Is Auth0?

• Definition: Platform for authentication and authorization as a service
• Owner: Okta (acquired Auth0 in 2021)
• Standards: Built on OAuth 2.0 and OpenID Connect (OIDC)
• Output: Returns JWTs (JSON Web Tokens) for stateless authentication

Why Auth0 Matters

• Security: No password storage, built-in brute-force protection, breached password detection
• Compliance: SOC2, HIPAA, GDPR ready out of the box
• Time Savings: Weeks of development reduced to hours
• Scalability: Handles millions of users without infrastructure management
• Standards-Based: OAuth 2.0 and OIDC ensure interoperability

Key Features: Universal Login, Social Connections (OAuth), Authentication Flow (5 steps)

Security: No Password Storage, Brute-Force Protection, Breached Password Detection, MFA, Compliance

Advanced Features: Rules & Actions, Organizations, Machine-to-Machine, Passwordless, Attack Protection

Pricing: Free (7,500 users), Essentials ($35/mo), Professional ($240/mo), Enterprise (custom)

Best Practices: Use Universal Login, Enable MFA, Monitor Logs, Rotate Secrets, Test Flows

Auth0 is the industry standard for authentication — providing enterprise-grade security and compliance out of the box, letting developers focus on core product instead of authentication complexity.