Free and open first
Best OAuth Server Software in 2026
- 32 apps
- Research read 23 Sept 2026
- How the order is worked out
- 1
Authgear
Free plan Open source AndroidAPIiPhone+2Authgear covers sign-in, user management, and SSO, with SDKs, APIs, and self-hosting support.
- 2
Ory
Free plan Open source APILinuxMac+3Ory combines identity capabilities with self-hosted and managed deployment choices. Teams needing B2B authentication should note that it is listed for Growth and Enterprise, not the lower two tiers.
- 3
Abblix OIDC Server
Free plan APILinuxSelf-hosted+2 - 4
Amazon Cognito
Free plan AndroidAPIiPhone+1Cognito combines application sign-in, federation, and access control with a wide set of AWS integrations.
- 5
Apereo CAS
Free plan APILinuxSelf-hosted+2 - 6
Asgardeo
Free plan AndroidAPIiPhone+2 - 7
Authelia
Free plan APILinuxSelf-hosted+1Authelia combines several authentication methods with policy-based access control and password resets.
- 8
authentik
Free plan APILinuxMac+3authentik covers a broad set of identity protocols and use cases, with a self-hosted deployment model.
- 9
Curity Identity Server
Free plan APILinuxMac+2 - 10
Descope
Free plan AndroidAPIiPhone+2Descope combines visual authentication-flow design with SDKs, APIs, and a broad range of authentication methods.
- 11
Dex
Free plan APILinuxSelf-hosted+1 - 12
Duende IdentityServer
Free plan AndroidAPIiPhone+5 - 13
Frontegg
Free plan AndroidAPIiPhone+1Frontegg combines customer sign-in, authorization, and B2B tenant controls with developer SDKs and an embedded admin portal.
- 14
Auth0 Guardian
Free plan AndroidiPhoneGuardian offers push approval and temporary OTPs, alongside options for app protection and localization.
- 15
FusionAuth
Free plan AndroidAPIiPhone+5FusionAuth offers identity management with multiple authentication methods, standards, and deployment options.
- 16
Google Cloud Identity
Free plan AndroidAPIiPhone+4Cloud Identity combines identity federation, app SSO, device management, and provisioning in a central service.
- 17
Casdoor
Free plan AndroidAPIExtension+6 - 18
Keycloak
Free plan APILinuxSelf-hosted+2Keycloak provides single sign-on, multiple authentication methods, directory synchronization, and fine-grained authorization policies as open-source software.
- 19
Kinde
Free plan AndroidAPIiPhone+1Choose Kinde if you are building a SaaS product and want authentication, access management, billing, and feature flags in one cloud platform.
- 20
LemonLDAP::NG
Free plan APILinuxSelf-hosted+1Choose LemonLDAP::NG if you need free, self-hosted SSO and federation across applications, with several integration methods and directory options.
- 21
Logto
Free plan AndroidAPIExtension+3Choose Logto if you need authentication and authorization for an app or SaaS product, with options for cloud or self-hosting and broad developer tooling.
- 22
Okta Customer Identity Cloud
Free plan AndroidAPIiPhone+4Auth0 covers user sign-in, single sign-on, passwordless access, and machine-to-machine authentication, with developer tools and deployment options.
- 23
OpenAM
Free plan APILinuxSelf-hosted+2 - 24
OpenIddict
Free plan AndroidAPIiPhone+5 - 25
Janssen Server
Free plan APILinuxSelf-hosted+1
#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price