Title: SMTPing Email Verifier Author: smtping Published: September 30, 2026 Last modified: September 30, 2026 --- Search plugins ![](https://ps.w.org/smtping-email-verifier/assets/banner-772x250.png?rev=3721298) ![](https://ps.w.org/smtping-email-verifier/assets/icon-256x256.png?rev=3721298) # SMTPing Email Verifier By [smtping](https://profiles.wordpress.org/smtping/) [Download](https://downloads.wordpress.org/plugin/smtping-email-verifier.1.5.4.zip) * [Details](https://wordpress.org/plugins/smtping-email-verifier/#description) * [Reviews](https://wordpress.org/plugins/smtping-email-verifier/#reviews) * [Installation](https://wordpress.org/plugins/smtping-email-verifier/#installation) * [Development](https://wordpress.org/plugins/smtping-email-verifier/#developers) [Support](https://wordpress.org/support/plugin/smtping-email-verifier/) ## Description SMTPing Email Verifier checks every email address when a form is submitted and rejects the ones you choose to block: mailboxes that do not exist, disposable addresses, spamtraps, blacklisted domains, known complainers and spambots. Cleaner signups mean fewer bounces, a healthier sender reputation and more accurate analytics. Verification runs on your server through the SMTPing API. Nothing changes in your forms’ front end, and your API key is never exposed to visitors. #### Two verification modes * **Full verification**: syntax, DNS, a live mailbox check and every threat list in one call. One credit per new address; `unknown` results are never charged. * **Fast checks**: spamtrap, disposable, spambot and complainer list lookups, answered in milliseconds. Ideal for high-traffic signup forms when you do not need to confirm the mailbox exists. #### You decide what gets blocked * Block by verdict: invalid, spamtrap, disposable, blacklisted, complainer, spambot, catch-all, valid catch-all, inbox full, unknown. * Block by signal: role-based addresses (info@, sales@), free providers (for B2B- only forms), likely typos. * Always-accept and always-block lists for addresses or whole domains. Lists are checked first and use no credit. * Custom message shown to visitors. #### Clean the addresses you already have One click on “Analyse the site” finds the addresses your site has already collected: WordPress users (including Ultimate Member, MemberPress, Paid Memberships Pro and BuddyPress members), comment authors, WooCommerce and Easy Digital Downloads customers, MailPoet and The Newsletter Plugin subscribers, and the stored entries of Gravity Forms, WPForms Pro, Fluent Forms, Formidable, Forminator, Elementor Pro and Contact Form 7 with Flamingo. Pick the sources, duplicates are removed, and the list is verified as one job. Nothing on your site is changed. The List tab verifies existing addresses without touching your site: paste up to 50 addresses and watch each verdict appear, or import a CSV file (read in the browser, only the addresses are sent). Filter the results by verdict and download them as CSV. #### A verification widget for your visitors Add `[smtping_verify]` to any page to let visitors check an address themselves. The check runs on your server, with optional per-visitor and site-wide daily limits to protect your credits. Off by default. #### A log you can export The Log tab lists every address checked by your forms and the widget, whatever the form plugin: date, address, verdict, accepted or blocked, and which form. Search, filter and export to CSV. Stored in your own database, pruned automatically (90 days by default), and covered by the WordPress personal data export and erase tools. #### Built to never break your site * Fails open: if the API is unreachable, the key is invalid or credits run out, forms keep accepting every address. * An admin notice tells you when verification is paused and why. * Results are cached (7 days by default) so repeat submissions do not spend credits. #### 32 supported plugins Each integration switches on automatically when its plugin is detected. **WordPress core**: registration (including multisite signup), comments, lost password. **Form builders**: Contact Form 7, WPForms, Gravity Forms, Elementor Pro forms, Fluent Forms, Ninja Forms, Forminator, Formidable Forms, MetForm, Everest Forms, JetFormBuilder, WS Form, SureForms, Kadence Blocks forms, Bit Form, HappyForms, BuddyForms, Contact Form by BestWebSoft. **Newsletters**: Mailchimp for WordPress (MC4WP), MailPoet, The Newsletter Plugin, Mail Mint. FluentCRM signup forms are built with Fluent Forms and are covered by that integration. **Membership and community**: Ultimate Member, MemberPress, Paid Memberships Pro, BuddyPress. **Checkout**: WooCommerce (classic checkout, block checkout, My Account registration), Easy Digital Downloads, SureCart. Developers can register more forms through the `smtping_ev_integration_classes` filter, and adjust any decision with `smtping_ev_should_block`. ### External services This plugin connects to the SMTPing API (https://smtping.com/) to verify email addresses. It is required for the plugin to work. No data is sent until you enter an API key. After that: * When a visitor submits a protected form, the email address they entered is sent to `https://api.smtping.com/api/v1/verify/single` (full mode) or `https://api. smtping.com/api/v1/checks/{check}` (fast mode). Your site URL is sent in the User-Agent header. * When you click “Test connection” in the settings, your credit balance is requested from `https://api.smtping.com/api/v1/credits`. * When you use “Test an email” in the settings, the address you type is sent to the same verification endpoints. * When a visitor uses the `[smtping_verify]` widget (off by default), the address they type is sent to the same verification endpoint. * When you use “Verify the addresses already on this site”, the addresses read from your database are sent to `https://api.smtping.com/api/v1/verify/bulk`. * When you verify a list in the List tab, the addresses are sent to `https://api. smtping.com/api/v1/verify/single` (pasted addresses) or `https://api.smtping. com/api/v1/verify/bulk` (CSV import). The service is provided by SMTPing. [Terms of use](https://smtping.com/terms), [Privacy policy](https://smtping.com/privacy). ## Installation 1. Install the plugin from the Plugins screen, or upload the `smtping-email-verifier` folder to `/wp-content/plugins/`. 2. Activate it. 3. Open Settings > SMTPing. 4. Paste your API key from the SMTPing dashboard and click “Test connection”. 5. Pick a verification mode, the verdicts to block and the forms to protect, then save. 6. Use “Test an email” to check your rules. ## FAQ ### Do I need an SMTPing account? Yes. Create one at https://smtping.com/ and generate an API key in the dashboard. The API uses the same credits as your dashboard. ### How many credits does it use? One credit per new address in full mode, and one per enabled check in fast mode. Results are reused for 7 days by default, `unknown` verdicts are free, and addresses on your allow or block lists never call the API. ### What happens if I run out of credits? Forms keep working and accept every address. An admin notice appears until you top up. ### Does it send an email to the address? No. SMTPing checks the mailbox at the mail server level without delivering any message. ### What is a spamtrap, and why block it? A spamtrap is an address that exists only to catch senders. Mailing one can get your domain or IP listed on blocklists, which is why it is blocked by default. ### Is it GDPR compliant? Addresses are sent to SMTPing only to verify them. A suggested paragraph is added to Settings > Privacy so you can mention the service in your privacy policy. The activity panel stores masked addresses only (j***@example.com). The Log tab stores full addresses in your own database for the retention period you choose, can be turned off, and is included in the WordPress personal data export and erase tools. ## Reviews There are no reviews for this plugin. ## Contributors & Developers “SMTPing Email Verifier” is open source software. The following people have contributed to this plugin. Contributors * [ smtping ](https://profiles.wordpress.org/smtping/) [Translate “SMTPing Email Verifier” into your language.](https://translate.wordpress.org/projects/wp-plugins/smtping-email-verifier) ### Interested in development? [Browse the code](https://plugins.trac.wordpress.org/browser/smtping-email-verifier/), check out the [SVN repository](https://plugins.svn.wordpress.org/smtping-email-verifier/), or subscribe to the [development log](https://plugins.trac.wordpress.org/log/smtping-email-verifier/) by [RSS](https://plugins.trac.wordpress.org/log/smtping-email-verifier/?limit=100&mode=stop_on_copy&format=rss). ## Changelog #### 1.5.4 * Bundled translation files removed; translations are delivered by translate.wordpress. org. #### 1.5.3 * List jobs: the progress line now shows the real API status, elapsed time and job ID. Temporary polling errors (409, 429, 5xx, network) retry automatically instead of stopping silently. * Renamed to SMTPing Email Verifier. #### 1.5.2 * Account alerts show only on the Dashboard, Plugins and SMTPing screens, and can be dismissed. #### 1.5.1 * Plugin Check fixes: every database query is fully prepared, widget preview output is escaped, explicit nonce checks, translations loaded without load_plugin_textdomain(). * Requires WordPress 6.2 or later. Tested up to 7.1. #### 1.5.0 * New “Verify the addresses already on this site”: scans users, comments, customers, subscribers and stored form entries, then verifies the unique addresses as one job, with results in the List tab. #### 1.4.3 * “Inbox full” moves to “Do not send” and is blocked by default. #### 1.4.2 * Fixed: the widget preview closed the settings form early, which mixed sections across tabs and stopped widget and log settings from saving. * Test an email, Activity and Resources now show on the Verification tab only; other tabs use the full width. #### 1.4.1 * Widget: the per-visitor daily limit is now optional (no limit by default). * Bundled PNG logos for all 29 integrations. #### 1.4.0 * New Log tab: every checked address from any supported form or the widget, searchable, filterable and exportable as CSV. Automatic cleanup and privacy tools support. * The site-wide daily cap of the widget is now optional (no limit by default). * Info bubbles explain the less obvious settings. * Paid Memberships Pro logo. #### 1.3.0 * New Widget tab and `[smtping_verify]` shortcode, with a live preview, custom texts and daily limits. * Bundled logos for Contact Form 7, WPForms, Gravity Forms, WooCommerce, Easy Digital Downloads, BuddyPress and Everest Forms. #### 1.2.0 * New List tab: paste up to 50 addresses, or import a CSV file (up to 10,000 addresses) as one bulk job. Results can be filtered by verdict and exported as CSV. * A short explanation under the title for each tab. * Integration logos, with a monogram when no logo is bundled. #### 1.1.1 * Settings split into two tabs: Verification and Forms. * Protected forms grouped by type, most installed plugins first. * Spambot addresses are blocked by default. #### 1.1.0 * 23 new integrations: Ninja Forms, Forminator, Formidable Forms, MetForm, Everest Forms, JetFormBuilder, WS Form, SureForms, Kadence Blocks forms, Bit Form, HappyForms, BuddyForms, Contact Form by BestWebSoft, Mailchimp for WordPress, MailPoet, The Newsletter Plugin, Mail Mint, Ultimate Member, MemberPress, Paid Memberships Pro, BuddyPress, Easy Digital Downloads, SureCart. * Settings list detected plugins first; the others are grouped below. #### 1.0.1 * API timeout raised to 15 seconds (minimum and default) so live mailbox checks can finish. Existing installs are upgraded automatically. * “Save settings” button next to the API key. * API errors in the test tool are shown in a neutral style instead of green. #### 1.0.0 * Initial release. ## Meta * Version **1.5.4** * Last updated **1 day ago** * Active installations **Fewer than 10** * WordPress version ** 6.2 or higher ** * Tested up to **7.1.2** * PHP version ** 7.4 or higher ** * Tags * [disposable email](https://wordpress.org/plugins/tags/disposable-email/)[email validation](https://wordpress.org/plugins/tags/email-validation/) [email verification](https://wordpress.org/plugins/tags/email-verification/)[spam protection](https://wordpress.org/plugins/tags/spam-protection/) [woocommerce](https://wordpress.org/plugins/tags/woocommerce/) * [Advanced View](https://wordpress.org/plugins/smtping-email-verifier/advanced/) ## Ratings No reviews have been submitted yet. [Your review](https://wordpress.org/support/plugin/smtping-email-verifier/reviews/#new-post) [See all reviews](https://wordpress.org/support/plugin/smtping-email-verifier/reviews/) ## Contributors * [ smtping ](https://profiles.wordpress.org/smtping/) ## Support Got something to say? Need help? [View support forum](https://wordpress.org/support/plugin/smtping-email-verifier/)