Maurice Hason

<p>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.</p>
<p><strong>Features:</strong></p>
<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.

dillilabs

<p>This plugin integrates with the Dilli Email Validation API (DEVA) to block fake or incorrectly formatted email addresses at form submission, ensuring higher-quality leads and significantly reducing spam.</p>
<p>This plugin requires an API Key which can be obtained for FREE by <a href="https://deva.dillilabs.com/register" rel="nofollow ugc">signing up here</a>. Learn more about Dilli Email Validation API <a href="https://www.dillilabs.com/products/email-validation-api/" rel="nofollow ugc">here</a>.</p>
<p>This plugin hooks directly into the WordPress core email validation function (<code>is_email()</code>), which is used by most major form plugins. That means it works out of the box with popular form builders like:</p>
<ul>
<li>Contact Form 7</li>
<li>WPForms</li>
<li>Gravity Forms</li>
<li>Ninja Forms</li>
<li>Jetpack/Grunion contact forms</li>
<li>WordPress registration forms</li>
<li>and many others.</li>
</ul>
<p>No need to modify your forms — just install and activate the plugin.</p>
<h4>Features</h4>
<ul>
<li>Validates email address format. Ex: email address <code>fooAtdillilabs.com</code> is invalid because of missing ‘@’</li>
<li>Checks for existence of MX records of the email address domain. Ex: <code>foobar@dlfkdlfkf.co</code> is invalid because no MX records exist for domain dlfkdlfkf.co.</li>
<li>Checks for Disposable/Temporary email addresses. Ex: user@mailinator.com is invalid because mailinator.com provides temporary shared temporary email inboxes.</li>
<li>Checks for conformity with ESP (Email Service Provider) grammar rules. Ex: <code>bob@yahoo.com</code> is invalid because Yahoo does not allow user part (<code>bob</code> in this case) to be less than 4 characters.</li>
<li>Checks for profanity in user part of email address. Ex: <code>f***you@gmail.com</code> is invalid.</li>
<li>Checks user and domain parts of an email address for known malicious patterns. Ex: <code>jondoe@gmail.com</code>, <code>foobar@yahoo.com</code>, <code>idontwanttogive@gmail.com</code> and <code>noemail@gmail.com</code> will be treated as invalid.</li>
<li>Checks email address domain against a known blacklist.</li>
<li>Checks email address against a known blacklist of frequently used email addresses for spam.</li>
<li>Checks for reserved domains. Ex: example.com is a reserved domain. Therefore, validemail@example.com is not allowed.</li>
<li>Checks for Role-based email addresses. Ex: info@someorganization.com will be treated as invalid.</li>
<li>Checks for safe domains. Restricts emails whose domains represents sites with adult content.</li>
<li>Checks for non-business email address.  Ex: *@gmail.com, *@yahoo.com, *@hotmail.com email addresses will be treated as invalid.</li>
<li>Checks the IP address of the user submitting the form against a known list of malicious IP addresses.</li>
<li>Add custom blocklist. You may request certain domains, emails and users to be blocked. </li>
</ul>
<h4>Available Languages</h4>
<ul>
<li>English</li>
<li>German (Deutsche)</li>
</ul>


Dilli Email Validator

Using the free 100 validation took 5 minutes having 10 logins only on my site.
Each login (not registration! login!!!) used 5 validations. I see no sense in validating logins (well, it makes sense for the provider asking 0.5 cents per validation). Even my admin user's (already logged in) ajax calls were validated each time.

And the worst is that it blocked valid users logging in with an email address from free email providers (not disposable).


BIG waste of money

Validates email addresses in real-time and blocks form submissions with invalid or fake emails. Reduce spam, fix typos, and capture quality leads.

Limesnip Simple2FA vs Dilli Email Validator