Dex vs FusionAuth
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
FusionAuth
Complete authentication and authorization platform
| Feature | Dex | FusionAuth |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 90 · Excellent | 70 · Good |
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | Go | Dockerfile |
| Setup difficulty | Medium | Medium |
| Min. RAM | 128 MB | 1,024 MB |
| Deployment | docker, kubernetes, binary | docker, kubernetes, bare-metal |
| GitHub stars | ★ 11,120 | ★ 241 |
| First released | 2016 | 2018 |
| Replaces | Okta, Auth0 | Auth0, Okta |
What are Dex and FusionAuth?
Dex
Dex is an identity service that uses OpenID Connect to drive authentication for other applications. It acts as a portal to other identity providers through connectors such as LDAP, SAML and GitHub.
- OIDC federation broker
- Connectors for LDAP, SAML and GitHub
- Popular in Kubernetes environments
- Lightweight and stateless
FusionAuth
FusionAuth is a self-hostable customer identity and access management platform supporting OAuth, OIDC, SAML, MFA, and user management. The community edition runs free on your own infrastructure.
- OAuth, OIDC and SAML support
- Multi-factor authentication
- User and tenant management
- Themable login pages
Dex vs FusionAuth: key differences
Dex is written in Go, while FusionAuth is built with Dockerfile. Dex is the lighter option, starting around 128 MB of RAM against 1,024 MB for FusionAuth. Dex is the more established project (first released 2016), while FusionAuth arrived in 2018. Dex has the considerably larger community, at 11,120 GitHub stars versus 241.
Why pick each one
Choose Dex if…
- Great Kubernetes integration
- Simple and reliable
Watch out for
- No user management of its own
Choose FusionAuth if…
- Released under the Apache-2.0 license
- First-class Docker support for quick deployment
- Kubernetes-ready with Helm charts available
- Written in Dockerfile
Frequently asked questions
Is Dex or FusionAuth better?
Neither is universally better. Dex has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Dex and FusionAuth free and open-source?
Yes. Dex is licensed under Apache-2.0 and FusionAuth under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Dex and FusionAuth with Docker?
Dex: yes. FusionAuth: yes.
Which is lighter on resources, Dex or FusionAuth?
Dex has the smaller minimum footprint at 128 MB of RAM, compared to about 1,024 MB for FusionAuth. Real-world usage depends on library size, user count, and enabled features.