Apereo CAS vs ZITADEL
A side-by-side comparison of two self-hosted identity & sso options — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Apereo CAS
Enterprise single sign-on server for web applications
VS
ZITADEL
Cloud-native identity infrastructure with multi-tenancy built in
| Feature | Apereo CAS | ZITADEL |
|---|---|---|
| Category | Identity & SSO | Identity & SSO |
| License | Apache-2.0 | Apache-2.0 |
| Language | Java | Go |
| Setup difficulty | Hard | Medium |
| Min. RAM | 1,024 MB | 512 MB |
| Deployment | docker, kubernetes, bare-metal | docker, kubernetes, binary |
| GitHub stars | ★ 11,354 | ★ 14,671 |
| First released | 2004 | 2020 |
| Replaces | Okta, Ping Identity | Auth0, Okta, Firebase Auth |
Why pick each one
Choose Apereo CAS if…
- Mature SSO with broad protocol support
- Widely adopted in academia
Frequently asked questions
Is Apereo CAS or ZITADEL better?
ZITADEL is the stronger all-round pick: it has both the larger community and the simpler medium setup. Consider Apereo CAS if its specific feature set fits your needs better.
Are Apereo CAS and ZITADEL free and open-source?
Yes. Apereo CAS is licensed under Apache-2.0 and ZITADEL under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Apereo CAS and ZITADEL with Docker?
Apereo CAS: yes. ZITADEL: yes.