Better Auth

Better Auth is an open-source authentication framework for TypeScript applications, configured in code rather than through a dashboard. It handles sessions, email verification, password reset, social sign-on, multi-tenancy with teams and roles, and enterprise requirements such as SSO, SAML 2.0, SCIM, and directory sync. It supports Next.js, Nuxt, SvelteKit, Astro, Hono, and other frameworks, with a plugin ecosystem covering passkeys, magic links, two-factor authentication, API keys, JWTs, anonymous authentication, and more. It also offers MCP auth, token exchange, and agent delegation for AI agents, alongside security features like bot detection, IP blocking, and email validation.

A paid managed infrastructure layer connects to self-hosted Better Auth and provides a dashboard for user, session, and organization management, auto-captured audit logs with filtering and SIEM log drain, and Sentinel real-time threat detection covering brute force, breached passwords, impossible travel, rate limiting, geo blocking, and suspicious IPs. It also includes transactional email and SMS with templates and abuse protection. The framework itself is free and open source; the infrastructure is packaged in a free Starter plan for evaluation, a Pro plan with unlimited dashboard seats and usage-based overages for audit events and security detections, and a custom Enterprise plan with custom retention, log drain, and support options.