ARK2FA vs OpenOTP Authentication Server

ARK2FA has no write-up on Specifiction yet; its figures are above.

OpenOTP Authentication Server is an authentication and identity management solution for multi-factor access, offered for cloud or on-premise deployment. It supports mobile push, smart-card certificates, secure magic links, YubiKey, FIDO2 passkeys and software tokens, alongside factors such as SMS, email, hardware tokens and OATH. Federated access options include SAML, OIDC and OAuth. Directory and identity integrations include Active Directory, LDAP, Entra ID, Okta, Google, Ping Identity and One Identity. The server also provides EAP network access control, mobile electronic signatures and mobile badging. Windows and macOS login plugins are listed, as are PAM plugins for Linux and macOS. OpenOTP is a WebADM sub-package and cannot be installed standalone. Pricing is on request, with a 30-day trial: the cloud trial supports up to 250 OpenOTP users and 50 SpanKey hosts; the on-premise trial supports up to 10 users and includes two active-active HA servers. The Freeware plan costs nothing and includes documentation and forum support only. Enterprise Edition is listed at €1.90 a year, and Enterprise Edition + SLA at €2.28 a year; both prices are shown per user/month based on 250 users and billed annually.