popularsizzle

A two-step verification plugin using the Time-based One-time Password Algorithm (TOTP), which can be used with an app or service like Google Authenticator.
<ul>
<li>Lightweight and fast: no classes are instantiated until required</li>
<li>No reliance or affiliation with any third-party service</li>
<li>No setup or config required: immediately enabled for all uses upon plugin activation</li>
<li>Automatically throttles multiple failed login attempts</li>
<li>Uses filters to allow modifying functionality or output</li>
<li>Requires PHP 7 or later</li>
<li>Built for WordPress 4.8 or later</li>
</ul>

Simple 2FA

A lightweight, zero-config TOTP 2FA plugin with automatic rate limiting. PHP 7 and WP 4.8 or later.

Helmi

SecureAuth Authenticator 2FA enhances your WordPress login security by requiring a time-based one-time password (TOTP) in addition to the regular username and password. The TOTP code is generated by an authenticator app on your mobile device, adding an extra layer of protection even if your password is compromised.
This plugin is lightweight, secure, and easy to use. It integrates directly into the user profile page to allow users to set up and manage their two-factor authentication with ease.
Features:
<ul>
<li>Adds a TOTP (Time-Based One-Time Password) field to the login form.</li>
<li>User-friendly 2FA setup available on each user’s profile page.</li>
<li>Generates secret keys and displays QR codes for scanning with mobile apps.</li>
<li>Compatible with apps like Google Authenticator, Microsoft Authenticator, and Authy.</li>
<li>Secure handling with nonce verification and input sanitization.</li>
<li>No external libraries required (except Google Chart API for QR code).</li>
</ul>

SecureAuth Authenticator 2FA

Adds TOTP-based two-factor authentication (2FA) via SecureAuth Authenticator to your WordPress login page.

Simple 2FA vs SecureAuth Authenticator 2FA