14 Open Source Alternatives to Auth0

BoxyHQ provides a comprehensive suite of security building blocks designed to accelerate time-to-market while ensuring robust protection. Its Jackson SSO tool supports SAML and OIDC protocols for seamless authentication, and its Directory Sync automates user and group provisioning using SCIM 2.0. The platform offers easy integration, customizable add-ons, and both SaaS and self-hosted deployment options to fit diverse enterprise needs.

SuperTokens offers comprehensive authentication features with support for email-password, social logins, and passwordless login methods such as magic links and OTPs. Built for rapid integration, it works seamlessly with over 25 frameworks and provides robust session management, user management dashboards, and customizable flows. Its unique architecture ensures easy migration from existing auth providers and reduces overall costs while maintaining high security and reliability.

Stack Auth delivers a comprehensive authentication solution that includes password, SSO, 2FA, and third-party OAuth integrations. Designed with robust APIs and pre-built UI components, it simplifies team management, permission settings, and JWT handling. With seamless Next.js integration and a headless SDK option, developers can quickly build and customize secure applications.

Ory offers a modular approach to identity management with extensive support for standards like OIDC, SAML, TOTP, and more. Its platform enables various deployment models including self-hosted open source, enterprise support, enterprise licensing, and the Ory Network. Designed for high scalability and uninterrupted performance, Ory provides comprehensive customization and integration capabilities that meet evolving security and UX requirements.

Authentik delivers a comprehensive identity solution by supporting a wide range of protocols including OAuth2, SAML2, LDAP, SCIM, RADIUS, and Kerberos. It simplifies implementation with pre-built workflows, customizable authentication templates, and robust APIs for seamless integration with modern infrastructures like Docker, Kubernetes, and Terraform. The tool enables secure Single Sign-On, Multi-factor Authentication, Conditional Access, and Zero Trust security, all managed through transparent, community-reviewed open source code.

Cerbos offers a plug-and-play, API-based approach to defining and enforcing access policies without cluttering your code. It supports both RBAC and ABAC models, integrates seamlessly with multiple languages and frameworks, and provides low-latency, distributed decision points for fast, secure runtime authorization. The solution not only simplifies policy management with a centralized administration hub but also adapts effortlessly to evolving business and regulatory needs.

Hanko provides embeddable components and APIs that enable developers to integrate secure user authentication quickly. Supporting a range of login methods—from passwordless with passkeys to optional passwords and social-only logins—Hanko adapts to your needs, delivering modern security with minimal integration effort. Its open source nature ensures you retain full control and flexibility, whether using the cloud or self-hosting.

Logto empowers developers to integrate secure and flexible identity solutions in minutes. The tool offers a comprehensive suite that includes password and passwordless authentication, social sign-in, MFA, enterprise SSO, and organizational features for multi-tenant apps. With seamless integration into over 20 modern frameworks, Logto enables you to build scalable and secure authentication workflows while focusing on core business logic.

UnKey redefines API management by offering a streamlined solution to quickly add API keys, enforce rate limits, and monitor usage analytics. With support for various languages and frameworks, comprehensive SDKs, and an intuitive REST API, it ensures global low latency and strong security through features like one-way hashed keys, IP whitelisting, and audit logs. Designed for both API-first and UI-first approaches, UnKey offers multi-cloud compatibility and proactive protection measures.

Fief streamlines the process of adding user authentication to your app with pre-built registration and login pages, alongside a complete users management dashboard. It handles complex protocols like OAuth2 and JWT effortlessly with easy-to-use APIs, libraries, and detailed tutorials. As an open-source solution, Fief allows self-hosting and complete control over your user data without vendor lock-in.

Authelia serves as a comprehensive identity and access management solution, acting as a middleware companion for common reverse proxies. Built with Go and React, it boasts a compressed container size under 20 megabytes and minimal memory footprint. The tool enforces login regulation to thwart brute force attacks, provides built-in password reset via email, and supports multiple second-factor methods including OTP, push notifications, and WebAuthn. Its granular authorization policies and scalability options, such as Kubernetes deployments, ensure efficient and secure access control.

Keycloak simplifies the process of managing authentication and access by acting as a centralized provider. It offers single sign-on to reduce repetitive logins, integrates with LDAP, Active Directory, and various social identity providers, and supports standard protocols such as OpenID Connect, OAuth 2.0, and SAML. Its admin console allows for centralized management of users, applications, and policies while the account management console empowers users to update profiles, configure two-factor authentication, and manage sessions.

Oso centralizes your authorization logic with Polar, its custom language built specifically for fine-grained access control. The tool decouples authorization from your business logic, delivering clear, readable policies and robust debugging support. Its flexible architecture supports cloud and local deployments, backed by extensive documentation and real-world testimonials from industry leaders.