Top 12 Open-Source Alternatives to CAS

The top open-source alternatives to CAS are Keycloak, Auth0, and FreeIPA. One of the criteria for ordering this list is the number of mentions that products have on reliable external sources. You can suggest additional sources through the form here.

Keycloak Landing Page
1

Keycloak

Open Source Identity and Access Management for modern Applications and Services.
Pricing:
- Open Source
#Identity And Access Management #Identity Provider #SSO 4 social mentions
Auth0 Landing Page
2

Auth0

Auth0 is a program for people to get authentication and authorization services for their own business use.
Pricing:
- Open Source
#Identity And Access Management #Identity Provider #SSO 175 social mentions
FreeIPA Landing Page
3

FreeIPA

FreeIPA is an integrated security information management solution combining Linux (Fedora), 389...
Pricing:
- Open Source
#Identity And Access Management #Cloud Computing #Cloud Storage
SimpleSAMLphp Landing Page
4

SimpleSAMLphp

SimpleSAMLphp is an OAuth authentication application written in native PHP.
Pricing:
- Open Source
#Identity And Access Management #Identity Provider #Monitoring Tools 4 social mentions
Ory Landing Page
5

Ory

Developer-first Access Management
Pricing:
- Open Source
#Identity And Access Management #Identity Provider #SSO 17 social mentions
FusionAuth Landing Page
6

FusionAuth

FusionAuth is a CIAM platform that is 100% free for unlimited users.
Pricing:
- Open Source
- Freemium
- Free Trial
#Authentication #User Management And Authentication #Multi-factor Authentication 29 social mentions
IdentityServer Landing Page
7

IdentityServer

An open-source, standards-compliant, and flexible OpenID Connect and OAuth 2.x framework for ASP.NET Core
Pricing:
- Open Source
#Identity Provider #Identity And Access Management #SSO 7 social mentions
authentik Landing Page
8

authentik

authentik is an open-source identity provider focused on flexibility and versatility.
Pricing:
- Open Source
#Identity And Access Management #Identity Provider #SSO 41 social mentions
Authelia Landing Page
9

Authelia

Authelia is an open-source authentication server providing SSO and two-factor for your applications running behind NGINX.
Pricing:
- Open Source
#Identity And Access Management #Authentication #SSO
ZITADEL Landing Page
10

ZITADEL

Identity infrastructure, simplified for you.
Pricing:
- Open Source
- Freemium
- $100.0 / Monthly (1'000 Daily Active Users included)
#Cyber Security #Identity And Access Management #Authentication 15 social mentions
Spring Security Landing Page
11

Spring Security

The Spring portfolio has many projects, including Spring Framework, Spring IO Platform, Spring Cloud, Spring Boot, Spring Data, Spring Security...
Pricing:
- Open Source
#Identity And Access Management #Identity Provider #Two Factor Authentication 8 social mentions
FreeRadius Landing Page
12

FreeRadius

FreeRADIUS is responsible for authenticating one third of all users on the Internet.
Pricing:
- Open Source
#Identity Provider #Identity And Access Management #SSO 7 social mentions