Duo Security Alternatives: 10 Options Compared, Including Free (2026)

What is Daito?

Discover Daito, a revolutionary web-based 2FA authenticator designed to streamline the management of TOTP 2FA tokens for both agile startups and established enterprises. Daito empowers organizations to effortlessly handle Time-based One-Time Passwords (TOTP) across their teams, providing a ...

What is Simple OTP?

Simple OTP is a passwordless authentication solution for websites, providing one-click two-factor authentication via OTP. It includes detection and prevention of malicious login activity to keep user accounts secure without adding friction to the login process.

What is GetOTP?

GetOTP makes setting up OTP verification a breeze. Our web API does the heavy lifting for you, so you can focus on developing your service. With just a few lines of code integration, GetOTP can let you generate passwords, choose between SMS, Email, Voice, or a combination of them for your OTP ...

What is Verify Now?

Verify Now (by Message Central) provides SMS-based OTP verification for businesses, with bulk OTP delivery APIs for high-volume authentication needs. It integrates into existing authentication workflows to reduce fraud and unauthorized access, and supports customizable delivery options across ...

What is Protectimus?

Introducing Protectimus, the ultimate two-factor authentication solution designed to streamline the security process for businesses. With the tagline "Two Factor Authentication Made Simple," Protectimus offers a seamless integration process that allows for quick setup with any business system. ...

What is Authsignal?

Authsignal is an MFA platform for development and fraud operations teams that combines behavioral signals—transaction velocity, windowed aggregations—with customizable authentication rules. It deploys in hours and lets teams define risk-based policies rather than applying static MFA to every ...

What is BehavioSec?

BehavioSec is a behavioral biometrics platform that authenticates users by analyzing patterns in how they type, swipe, and interact — without requiring passwords, one-time codes, or push notifications. It integrates with existing applications to detect bots and account takeover attempts without ...

What is NoPass.me?

NoPass.me is an open-source, accountless authentication solution designed to simplify multi-factor authentication (MFA). With secure identity verification available with just one API call, the software provides secure, one-time passwords easy for developers, small, and medium businesses to ...

What is OTPfy?

OTPfy is an effective SaaS platform that simplifies the process of safeguarding applications. It enables you to generate One Time Password codes and Magic Links to protect your app functionality without taking up valuable engineering time and resources. OTPfy helps you secure any part of your ...

What is VerifyKit?

VerifyKit, the ultimate solution for cutting down on SMS verification costs. Get users back into your app in just 6 seconds by letting them choose their preferred verification method. Never worry again about costly sms verification. With VerifyKit, verification codes can be sent instantly ...