Miquel Colomer

This plugin uses the uProc for WordPress API <a href="https://uproc.io" rel="nofollow ugc">https://uproc.io</a> to check if an email address really exists or not.
The plugin integrates with the is_email() function of WordPress. It works seamlessly with:
<ul>
<li>Contact Form 7</li>
<li>Jetpack/Grunion</li>
<li>WordPress registration forms</li>
<li>and with any other form which uses the is_email() function (no changes required).</li>
</ul>
The plugin can also be integrated into 3rd party forms that do not use the is_email() function.
<h4>How does it work?</h4>
The uProc API real-time validation process includes all of the following tests:
<ul>
<li>Syntax verification (IETF/RFC standard conformance)</li>
<li>DNS validation, including MX record lookup</li>
<li>Disposable email address (DEA) detection</li>
<li>Misspelled domain detection to prevent Typosquatting</li>
<li>Freemail address detection</li>
<li>SMTP connection and availability checking</li>
<li>Temporary unavailability detection</li>
<li>Mailbox existence checking</li>
<li>Catch-All testing</li>
<li>Greylisting detection</li>
<li>Block free domain emails (like Gmail, Hotmail, Yahoo, …)</li>
<li>Avoid email validations on Woocommerce orders</li>
</ul>
The plugin requires an API Key (free, no credit card required): 
<a href="https://app.uproc.io/#/signup" rel="nofollow ugc">https://app.uproc.io/#/signup</a>
We do not send any email to the recipient address during the entire validation process. All processing is done on our servers, your IP addresses and domains are not affected in any way by the Email-Validator service – absolutely no blacklisting risk for your IPs and domains.
Data Protection and Privacy Policy: see the Frequently Asked Questions section.
<h3>What is uProc</h3>
uProc is a SaaS platform where you can check or enrich any available field in your database. Please, check our catalog at 
<a href="https://app.uproc.io/#/tools" rel="nofollow ugc">https://app.uproc.io/#/tools</a> 
to find the right tool for you.
Next fields can be processed with our catalog: 
* Audio: speeches 
* Communication: Email, Mobile, Phone 
* Company: Cif, Name, Employee 
* Finance: Credit card, Account, Currency 
* Geographical: Country, City, Coordinates 
* Image: Screenshot, EXIF 
* Internet: Domain, IP, URI 
* Personal: Name, Surname, Gender 
* Product: EAN, UPC, ASIN, GTIN, ISBN 
* Security: Password, MD5, Luhn 
* Text: Uppercase, Lowercase, Lists

uProc for WordPress

I hope this plugin will be useful for your site.

You can validate emails on registration or comments.
Some cash is added to your account by default to test it.

The weak point: No other validation is supported yet when lots are available in the service catalog.

This will be solved soon. Mobile and landline phones validations are needed in my WordPress site.

Nice plugin, useful for my site

With the uProc for Wordpress plugin you can easily verify if an email address really exists and is valid. Additionally, you can check all existing too …

joern.zaefferer

Ever got annoyed when submitting a comment on a wordpress blog and just getting a blank page with a error message like “please fill out required fields” and nothing else? This plugin aims to help by adding validation to the comment form. When a user submits the form and something is missing, an appropiate message is displayed and individual fields are highlighted. When the email or url is in an incorrect format, a message is displayed accordingly.
Why should you install it? Because you care for comments and want to help users reduce mistakes that hold them off from commenting at all.
Whats the technology used? <a href="http://jquery.com" rel="nofollow ugc">jQuery</a> and the <a href="http://bassistance.de/jquery-plugins/jquery-plugin-validation/" rel="nofollow ugc">jQuery Validation plugin</a> with a few customizations to make it fit into the standard WordPress theme.
Is it compatible with other plugins? The plugin is tested with the <a href="https://wordpress.org/extend/plugins/draw-comments/" rel="ugc">Draw Comments</a> plugin and works, though the performance is slightly degraded. Other plugins haven’t yet been tested.

Comment Validation

This plugin adds client-side validation to the Wordpress comment form, using the jQuery validation plugin.

uProc for WordPress vs Comment Validation