Apereo CAS vs authentik
Apereo CAS
apereo.github.io
authentik
goauthentik.ioSide by side
| Figure | Apereo CAS | authentik |
|---|---|---|
| Price from | Free | $5/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | — | Yes |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 4 |
| Spec score · OAuth Server Software | 8.6 (#6) | 8.5 (#9) |
| Authentication | Authentication sources include LDAP, databases, X.509, SPNEGO, JAAS, JWT, RADIUS, and MongoDB. | It supports multi-factor authentication with TOTP and WebAuthn/passkeys, including hardware or software authenticators. |
| Deployment | CAS is a Java web application that requires JDK 25 for building and deployment according to its installation requirements. | authentik can run on customers’ own infrastructure, including Docker and Kubernetes, and the pricing FAQ says there is currently no hosted version. |
| Protocols | It supports CAS, SAML, WS-Federation, OAuth 2.0, OpenID Connect, and REST protocols. | Listed protocols include OAuth2/OpenID Connect, SAML2, LDAP, RADIUS, SCIM, and Kerberos. |
| Support | Community support is voluntary and has no SLAs or guarantees; the project points users to professional support agreements from commercial providers. | The open-source plan lists community Discord and no support; paid support is offered as part of enterprise software subscriptions, with ticket support for Enterprise subscriptions over $1k. |
Plans
authentik
- FreeFree
- Enterprise$5 a month
- Open SourceFree
- Enterprise Plus$20,000 a year
In their own words
Apereo CAS
Apereo CAS has no write-up on Specifiction yet; its figures are above.
authentik
authentik is an open-source, self-hostable identity and access management product for workforce single sign-on, customer identity, zero-trust security, legacy application integration and API security. It supports OAuth2/OpenID Connect, SAML2, LDAP, RADIUS, SCIM and Kerberos, as well as WS-Federation. MFA options include TOTP, WebAuthn/passkeys, email, SMS, Duo and static tokens. Access policies can consider factors such as user attributes, time and location. Security features include audit logging, session binding, GeoIP and impossible-travel detection, and client certificate authentication with mTLS. It can run on customer infrastructure, including Docker and Kubernetes; the pricing FAQ says there is no hosted version currently. The authentik Agent integrates with Windows, macOS and Linux for local device login and CLI authentication. A free open-source plan includes community Discord support but no product support. Enterprise costs $5 a month, billed annually, at $5 per user per month; external users are $0.02 per month and service accounts have no cost.