Aegis Authenticator is a free, secure and open source app to manage your 2-step verification tokens for your online services.




The best open source alternative to OTPClient is Aegis Authenticator. If that doesn't suit you, our users have ranked more than 25 alternatives to OTPClient and many of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to OTPClient are Proton Authenticator, Bitwarden Authenticator, 2FA Authenticator (2FAS) and FreeOTP.
Aegis Authenticator is a free, secure and open source app to manage your 2-step verification tokens for your online services.




Protect your accounts with Proton Authenticator, a private and secure cross-device two-factor authentication (2FA) that works offline. Created by Proton, the creators of Proton Mail, Proton VPN, Proton Drive, and Proton Pass.




Bitwarden Authenticator generates verification codes for two-factor authentication, ensuring your identity is verified when you log into accounts.




2FAS Authenticator is a simple and free application for Two Factor Authentication (2FA Authentication) which generates Time-based One-time Passwords (TOTP) and PUSH authentication*.




FreeOTP is a two-factor authentication application for systems utilizing one-time password protocols with support for Android (6 or later) and iOS (11 or later). Tokens can be added easily by scanning a QR-code or by manually entering in the token configuration.




A free open-source two factor authentication app for Android. It features encrypted backups, icons, categories and a high level of customisation. It also has a Wear OS companion app.




Authenticator generates two-factor authentication (2FA) codes in your browser. Use it to add an extra layer of security to your online accounts.



OnlyKey is an open source alternative to YubiKey. OnlyKey natively supports: a hardware password manager, multiple two-factor methods (FIDO2, TOTP, and Yubico® OTP), passwordless SSH login, and OpenPGP.




Mauth (pronounced Moth) is a Two-Factor Authentication app with support for TOTP and HOTP (coming soon) and compatibility with Google Authenticator.




Keysmith is a token generator for your two-factor authentication (2FA) logins. It supports time and hash-based one-time passwords (TOTP/HOTP).

2fast (acronym for two factor authenticator supporting TOTP) is the first free, open source, two factor authenticator for Windows and Android with the ability to store the sensitive data encrypted at a place of your choice instead of a 3rd party cloud location.


Gnome Authenticator is a desktop 2FA code generator for Linux desktops, like Ubuntu.
