Authy 
Duo Security 
Google Authenticator About privacyIDEA
privacyIDEA is an open-source multi-factor authentication server developed on GitHub under AGPLv3 and backed commercially by NetKnights GmbH in Kassel, Germany. It supports a broad range of tokens — HOTP/TOTP, SMS, email, push, SSH keys, X.509, YubiKey, Nitrokey, U2F and FIDO2 — and integrates with Active Directory, Entra ID, Keycloak and LDAP. The community edition is free; NetKnights sells an Enterprise Edition with packages for Ubuntu LTS and RHEL/CentOS plus support and SLAs.
Quick facts
Pricing model
Open source
Free trial
—
Open source
Yes
Self-hostable
Yes
Public API
No
Target audience
B2B
Company size fit
All
DPA available
Yes
Data stored in EU
Yes
