Maurice Hason

Limesnip Simple2FA adds email-based two-factor authentication to your site. After entering their username and password, users receive a 6-digit verification code via email that they must enter to complete login.
Features:
<ul>
<li>Email-based 2FA – no authenticator app required</li>
<li>Clean, Linear-inspired verification UI</li>
<li>Auto-advancing digit inputs with paste support</li>
<li>Auto-submit when all digits are entered</li>
<li>Role-based enforcement – choose which roles require 2FA</li>
<li>Configurable code expiration and max attempts</li>
<li>Optional “Remember this device” feature</li>
<li>HTML and plain text email support</li>
<li>Secure code storage (SHA-256 hashed)</li>
<li>Fully responsive design</li>
</ul>

Limesnip Simple2FA

Simple email-based two-factor authentication for WordPress. Adds a clean, Linear-inspired verification screen to your login flow.

zerobounce

Need an email validation tool to block invalid and high-risk emails on your WordPress website?
The ZeroBounce email verification plugin assists users by validating email addresses entered into your registration forms, comments sections, eCommerce shops, and more. Install the plugin, connect your API key, and select the forms you want to monitor with email validation.
<h3>Key Features</h3>
<ul>
<li>Automated real-time email validation – Automatically prevent selected email types from creating accounts, leaving comments, or signing up</li>
<li>Detect more than 30+ email address types – Including invalid, abuse, disposable, spam trap, toxic domains, catch-all, and more</li>
<li>Choose what to accept – Create your own rules for email validation and disallow emails based on status</li>
<li>Email verification for 9 form types – Easily select which forms you want to protect with email validation</li>
<li>Fast manual email validation – Verify any email address in the tools section using our interactive form</li>
<li>Email validation API logs – Keep track of monthly email verifications, including status, sub-status, IP, date, and credits used</li>
</ul>
<h3>Benefits</h3>
<ul>
<li>Keep your email list clean & accurate</li>
<li>Reduce your email bounce rate</li>
<li>Boost your inbox placement</li>
<li>Protect your email sender reputation</li>
<li>Improve email deliverability</li>
<li>Eliminate fraudulent, untrustworthy shoppers</li>
<li>Block spammers and spoofers</li>
<li>Keep your comments section clean</li>
</ul>
<h3>Supported Forms/Plugins</h3>
<ul>
<li>Contact Form 7</li>
<li>WPForms</li>
<li>Ninja Forms</li>
<li>Formidable Forms</li>
<li>WooCommerce</li>
<li>WordPress Post Comments</li>
<li>WordPress Registration</li>
<li>MC4WP: Mailchimp for WordPress</li>
<li>Gravity Forms</li>
<li>Fluent Forms</li>
<li>WS Forms</li>
<li>Mailster Forms</li>
<li>Forminator Forms</li>
</ul>
And more support is being added gradually.

ZeroBounce Email Verification & Validation


I have tested this plugin on several of my personal and business websites, it's awesome. No more spam and fake signups. Service pricing is also decent. Recommended.


Excellent in blocking SPAM


You have a problem with NF form validation. It detects html fields that contains emails (eg mailto links) as email fields and validates those.



if (!empty($value) && is_string($value) && preg_match('/@.+\./', $value) && !str_contains($value, "\n") && !str_contains($value, '\n')) {// rest of the code}



Your approach needs to be changed to:



if (!empty($value) && is_string($value) && preg_match('/@.+\./', $value) && !preg_match('/mailto:/i', $value)) {  $ninjaForm = new Zerobounce_Email_Validator_Form_Public('ninjaforms', $form_data['id']);   // rest of the code}



This should be safer to validate only email addresses (or use a better regex).


Ninja Forms problem

ZeroBounce validates emails on your WordPress site in real-time, blocking invalid and risky emails to improve deliverability and reduce bounce rates.

Limesnip Simple2FA vs ZeroBounce Email Verification & Validation