MailboxValidator Email Validator


This email validation plugin helps you to block disposable email, free email, invalid email or role-based email from using your services or input form.

It helps to block spam, temporary emails and invalid email address messing around your site. You don’t have to master the hard part of adding shortcode into page source to use this plugin, but to activate, configure and you’re ready to prevent all spam signups from invalid email addresses.

You can sign up for a free API key at, that will allow you to validate up to 300 emails every month for free!

Supported Plugins

  • Contact Form 7
  • MailChimp
  • Formidable forms
  • WooCommerce
  • JetPack comments and contact form
  • Profile Builder
  • Ultimate Member registration form
  • Users Ultra registration form
  • Theme My Login
  • WP-Members
  • Paid Membership Pro
  • Visual Form Builder
  • Easy Digital Downloads registration form
  • and other plugins that yet come under our radar

Key Features

  • Accurate email verification result
  • Block invalid email.
  • Block disposable email.
  • Block free email.
  • Block role email.
  • Support domain blacklisting.

This email verification plugin needs a MailboxValidator API key to work. You can get a free API from MailboxValidator.


  • Setting page for MailboxValidator Email Validator. At here you can add your MailboxValidator API Key and switch on or off the valid, disposable and free email validator.
  • Statistics page for MailboxValidator Email Validator. At here you can view the total amount of email address blocked by MailboxValidator Email Validator in last 30 days.
  • Example of Contact Form 7 email validation.
  • Example of Mailchimp for WordPress email validation.
  • Example of Formidable Forms email validation.
  • Example of Caldera Forms email validation.
  • Example of Contact Form by BestWebSoft email validation.
  • Example of BuddyPress email validation.
  • Example of Profile Builder email validation.
  • Example of WooCommerce registration form email validation.


Installation using WordPress dashboard

  1. Select Plugins -> Add New.
  2. Search for “MailboxValidator Email Validator”.
  3. Click on Install Now to install the plugin.
  4. Click on Activate button to activate the plugin.
  5. Get your MailboxValidator API key before start using the plugin.
  6. Configure the plugin settings, including your API key, domain blacklist and switch on or off the valid, disposable and free and role-based email validator, and design custom error messages.

Manual Installation

  1. Upload the plugin files to the /wp-content/plugins/mailboxvalidatoremail-validator directory.
  2. Activate the plugin through the ‘Plugins’ screen in WordPress
  3. Get your MailboxValidator API key through here.
  4. Configure the plugin settings, including your API key, domain blacklist and switch on or off the valid, disposable, free and role-based email validator, and design custom error messages.

नेहमी विचारले जाणारे प्रश्न

How can this plugin help to validate form details?

This plugin will validate those email and make sure that it is valid or not belong to disposable, free email or role-based. In other words, it will reject those email which is invalid, disposable or free email, depends on your settings.

What is role-based email address?

A role-based email address is the email address that front part like admin@, sales@, support@ and so on.

Do I need an API key to use this plugin?

Yes. You can sign up for a FREE API key from MailboxValidator to use this plugin.

Unable to find your answer here?

Send us email at


फेब्रुवारी 20, 2022
We lost customers because their mail address was marked as invalid and the order couldn’t get through. They sent me a mail from that address proving that the address did actually work. We immediately uninstalled this plugin, it’s not trustworthy.
सर्व 1 पुनरावलोकन वाचा

योगदानकर्ते आणि विकसक

“MailboxValidator Email Validator” हे मुक्त स्रोत सॉफ्टवेअर आहे. पुढील लोक या प्लगइनच्या निर्मितीत योगदान केले आहे.


“MailboxValidator Email Validator” 1 लोकॅलमध्ये भाषांतरित केले आहे. अनुवादकांना त्यांच्या योगदानाबद्दल धन्यवाद.

भाषांतर करा “MailboxValidator Email Validator” तुमच्या भाषेत.

विकासातील आग्रह?

कोड ब्राउझ करा, SVN संग्रहालय तपासा, किंवा विकास लॉग च्या RSS द्वारे सदस्यता घ्या.

बदलांची यादी


  • Tested up to WordPress 6.5.


  • Add new checking to prevent the abuse of the API.


  • Update to use v2 for MailboxValidator API through MailboxValiator PHP SDK, and tested with WordPress 6.4.1.


  • Tested with WordPress 6.2.


  • Tested with WordPress 6.1.


  • Tested with WordPress 6.0.


  • Minor fix.


  • Tested with WordPress 5.9.


  • Minor fix.


  • Code restructure and UI update.
  • Added chart for email address blocked statistics.


  • Added custom error message feature.


  • Minor Improvements.


  • Updated readme file description.


  • Tested with WordPress 5.8.


  • Updated tested WordPress version.


  • Minor issue fix.


  • Added supported plugin.


  • Added missing vendor folder.


  • Used MailboxValidator PHP SDK to get API result.


  • Tested with WordPress 5.6.


  • Removed unwanted line.


  • Update stable tag.


  • Added languages folder, and Chinese language.


  • Updated text displayed.


  • Removed the minimum WordPress version required.


  • Tested with WordPress 5.5.


  • Update FAQ section in readme.


  • Minor improvement for validation process.


  • Display more information about MailboxValidator API plan.


  • Show the remaining credits in the plugin setting page.
  • Add the option to enable/disable the debugging log.


  • Added source parameter to keep track for API calling.


  • Reformat the code to follow the WordPress Coding Standards.
  • Added js files that are missing.
  • Changed descriptions in settings page.


  • Added feedback feature when deactivate the plugin.
  • Reorganize the js files.


  • Added block role-based email address feature.


  • Added domain blacklisting feature.


  • Fixed minor error.


  • Initial Release