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




OnlyKey is described as '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' and is a Authenticator in the security & privacy category. There are more than 25 alternatives to OnlyKey for a variety of platforms, including Android, iPhone, Linux, Mac and iPad apps. The best OnlyKey alternative is Bitwarden Authenticator, which is both free and Open Source. Other great apps like OnlyKey are Authy, Google Authenticator, andOTP and YubiKey.
Bitwarden Authenticator generates verification codes for two-factor authentication, ensuring your identity is verified when you log into accounts.




Manage two-factor authentication seamlessly across various platforms with secure cloud backups and offline access. From Gmail to LastPass, enhance security effortlessly. Sync multiple devices securely and protect sensitive data with robust encryption.




Google Authenticator generates 2-Step Verification codes on your phone.




It implements Time-based One-time Passwords (TOTP) and HMAC-Based One-Time Passwords (HOTP). Simply scan the QR code and login with the generated 6-digit code.




The multi-protocol security key offers the highest assurance, protecting devices with passwordless workflows and strong 2FA against phishing. It plugs into computers, tablets, and mobile devices, integrates PIN or biometric for identity verification, and reduces helpdesk costs.



Provides robust USB-based encryption, digital signing, and secure login with hardware-level secret key storage, user-defined PIN, tamper-proof smart card, open source design, email and data encryption compatibility, virus protection, and multi-platform support.


OVault is a super simple OTP app that lets you view and manage OTPs for all your accounts. Set up OTPs by scanning QR codes with your devices Camera App, or by manually providing the OTP secret to the app.




Sign in is easy, convenient, and secure when you use Microsoft Authenticator. Use your phone, not your password, to log into your Microsoft account. You simply have to enter your username, then approve the notification sent to your phone.




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

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

Allthenticator unifies digital and physical access with one smartphone-based identity. Users log in to systems and unlock doors via proximity. Supports SSH keys, passkeys, OTP, and peer-based recovery—all managed from a single admin dashboard.




Etopa is a two-factor-authentication app, which runs as a web server and can be accessed using a web browser or using an Android app. You can use the Etopa.de instance or host your own.



