Auth.js vs FusionAuth: Features, Pricing and User Reviews 2026
Compare features, pricing, reviews, and more to make an informed decision
Auth.js
Auth.js is a free, open-source authentication library for web applications, supporting OAuth, magic links, and credentials across multiple frameworks.
FusionAuth
FusionAuth is a developer-first authentication platform offering flexible login, single sign-on, and user management with self-hosted or cloud deployment.
Auth.js
Auth.js is a free, open-source authentication library for web applications, supporting OAuth, magic links, and credentials across multiple frameworks.
FusionAuth
FusionAuth is a developer-first authentication platform offering flexible login, single sign-on, and user management with self-hosted or cloud deployment.
Auth.js
OAuth 2.0 and OpenID Connect support
80+ pre-configured authentication providers
Magic link email authentication
Username and password credentials
WebAuthn passwordless login
Multiple framework support (Next.js, SvelteKit, Express)
Database adapters for major databases
JWT or database sessions
Built-in security features
Custom page support
TypeScript ready
Open source and free
FusionAuth
Password and passwordless authentication options
Social login integration (Google, Facebook, Apple, LinkedIn)
Single sign-on across applications
Multi-factor authentication and biometric support
Breached password detection
User registration and profile management
Role-based permissions and access control
REST APIs and SDK libraries
Self-hosted or cloud deployment
Customizable login pages and email templates
Auth.js
Auth.js is completely free to use with no pricing tiers or hidden costs. As an open-source project, it is licensed under the ISC license, which allows anyone to use, modify, and distribute the software freely for both personal and commercial projects.
There are no subscription fees, no usage limits, and no charges for any features. All capabilities, including support for unlimited providers, database integrations, and advanced security features, are available at no cost. This makes Auth.js an excellent choice for projects of any size, from small personal websites to large enterprise applications.
The project is maintained by a community of contributors and is now part of Better Auth Inc. Developers can contribute to the project, report issues, and access community support through GitHub discussions completely free of charge.
FusionAuth
FusionAuth offers flexible pricing to match different needs and deployment preferences.
Self-Hosted is completely free with unlimited users. Download and run FusionAuth on your own infrastructure with no ongoing costs. You get all core authentication features, making it perfect for development, testing, and production environments where you want full control.
Basic Plan starts at $37 per month and provides a single cloud server instance, ideal for development and testing environments. It includes one custom domain and basic cloud hosting.
Business Plan costs $225 per month and offers a dedicated server with nightly backups, availability across multiple zones, and support for up to five custom domains. This plan suits most production applications.
High Availability Plan begins at $500 per month with redundant servers, configurable backups, and up to 99.99% uptime guarantee with the Enterprise support plan. This includes 20 custom domains and deployment in any AWS region.