smtpdkim

<p>🚨 Are your WordPress emails going to spam?</p>
<p>Without proper email authentication, services like Gmail, Outlook, and Yahoo may block or mark your emails as spam. This results in lost notifications, password resets, and order emails.</p>
<p>SignEmail SMTP helps you send reliable WordPress emails using professional SMTP servers, with optional DKIM authentication support.</p>
<h4>Why email authentication matters</h4>
<p>Modern email providers require proper authentication (SPF, DKIM, DMARC) to trust your messages. Without it, even valid emails may be filtered as spam.</p>
<h4>📬 SMTP Email Delivery</h4>
<p>Send all WordPress emails through reliable SMTP servers instead of PHP mail(), improving deliverability and consistency.</p>
<h4>⚙️ Universal SMTP Compatibility</h4>
<p>Compatible with Gmail, Outlook, Brevo, cPanel, OVH, Infomaniak, SiteGround, GoDaddy, Bluehost, WP Engine, Kinsta, Namecheap, Gandi, o2switch, LWS, and more.</p>
<h4>🔍 Email Testing Tool</h4>
<p>Send test emails to verify inbox delivery and diagnose spam placement in real conditions.</p>
<h4>🔎 DNS Diagnostic Tool</h4>
<p>Check SPF, DKIM, and DMARC records using Cloudflare DNS-over-HTTPS.</p>
<h4>🔒 Secure Storage</h4>
<p>SMTP credentials are encrypted using AES-256-CBC and stored securely in your WordPress database.</p>
<h4>🌐 Multilingual Support</h4>
<p>Full French and English interface with per-user language selection.</p>
<h4>SMTP Features</h4>
<ul>
<li>Full SMTP configuration (SSL / TLS / STARTTLS / None)</li>
<li>Encrypted password storage (AES-256-CBC)</li>
<li>Force sender email and name</li>
<li>Debug logging system</li>
<li>Built-in email test tool</li>
<li>DNS verification (SPF / DKIM / DMARC)</li>
<li>Compatible with WooCommerce, CF7, Elementor, Gravity Forms, BuddyPress, LearnDash, etc.</li>
<li>Fully intercepts wp_mail()</li>
</ul>
<h4>Optional DKIM Support</h4>
<p>DKIM email signing is available in the <strong>Premium version</strong> of this plugin — smtp-dkim.com.</p>
<ul>
<li>Works alongside SMTP delivery</li>
<li>Improves inbox trust and deliverability</li>
</ul>
<h4>Security & Privacy</h4>
<ul>
<li>SMTP credentials encrypted before storage</li>
<li>No credentials are sent to external servers</li>
<li>License verification (if used) only transmits license key + domain name</li>
<li>No email content is ever transmitted externally</li>
</ul>
<h3>External Services</h3>
<p>This plugin connects to the following external services:</p>
<h4>1. Cloudflare DNS-over-HTTPS</h4>
<p>Used by the DNS Diagnostic tool to check SPF, DKIM, and DMARC records.</p>
<ul>
<li>Service: Cloudflare DNS-over-HTTPS API</li>
<li>Endpoint: https://cloudflare-dns.com/dns-query</li>
<li>Data sent: Domain name and DKIM selector (no personal data)</li>
<li>When: Only when the admin manually runs the DNS diagnostic tool</li>
<li>Terms of Service: https://www.cloudflare.com/terms/</li>
<li>Privacy Policy: https://www.cloudflare.com/privacypolicy/</li>
</ul>
<h4>2. User-configured SMTP server</h4>
<p>Used to deliver WordPress emails via the SMTP protocol.</p>
<ul>
<li>Service: Any SMTP server configured by the site administrator (e.g. Gmail, Outlook, Brevo, cPanel)</li>
<li>Data sent: Email content as configured by WordPress (wp_mail)</li>
<li>When: Every time WordPress sends an email</li>
<li>Terms of Service and Privacy Policy: Refer to your SMTP provider</li>
</ul>
<h4>3. smtp-dkim.com — License validation (Premium version only)</h4>
<p>The Premium version validates the license key to enable DKIM signing.</p>
<ul>
<li>Endpoint: https://smtp-dkim.com/wp-json/sdlm/v1/validate</li>
<li>Data sent: License key + domain name only — no email content, no SMTP credentials</li>
<li>When: On plugin activation and periodically in the background</li>
<li>Terms of Service: https://smtp-dkim.com/politique-de-confidentialite/</li>
<li>Privacy Policy: https://smtp-dkim.com/politique-de-confidentialite/</li>
</ul>
<p>Note: The free version available on WordPress.org does not include license validation or DKIM signing.</p>


SignEmail SMTP & DNS Diagnostic

Stop WordPress emails from going to spam. Send emails via SMTP and check SPF, DKIM, DMARC records to improve email deliverability.

Antonino Piazza

Stefano Varesi

Nicola VoT Selenu

<p>Our Deliverability Plugin for WordPress allows you to easily authenticate emails generated from your website with a DKIM signature.</p>
<p>But our Deliverability Plugin does much more than that! In fact, it’s packed with incredible email security and email deliverability features such as:</p>
<ul>
<li>SPF authentication check, monitor and troubleshoot</li>
<li>DKIM authentication implementation, check, monitor and troubleshoot</li>
<li>DMARC authentication check, monitor and troubleshoot</li>
</ul>
<p>It’s always a good practice to authenticate your domain, but if your domain has a DMARC record and your website runs on WordPress you almost certainly need this plugin.</p>
<p>The Deliverability plugin will take your Email Deliverability to a whole new level.</p>
<p>This plugin is designed and written by experts and is easy to use and understand.</p>
<p>It reduces security risk by checking for shortcomings in your email setup, and by implementing and enforcing the latest recommended Email security practices and techniques.</p>
<p>Fully compatible with Contact-Form 7, WPForms, BuddyPress, WP Mail SMTP and more.</p>


Deliverability – pass DKIM, SPF, DMARC & more


Of course I might be biased, but I believe this is a must-to-have plugin to protect your brand and digital identity or just to increase the chances to land in the recipient's inbox.


A must to have plugin :)


Excellent dashboard with lot of informations. I used it to fix the deliverability configuration of my website. After that, I didn't receive any complaint from my users about my emails marked as spam in their inbox.



Really effective!


Great plugin


The plugin is very well made and the code is organized and clean which is truly a plus, an added value in the sea of plugins that often bring down the performance of websites due to the poor quality of the written code.



It helps a lot in his mission. Especially the less experienced, but also professionals will have to do less expensive work to optimize mail delivery.



I highly recommend trying it to all users who have problems with mail delivery from their WordPress site and who have to struggle with this annoying problem every day.



A Swiss Army Knife for optimizing email deliverability, with practical tips that guide you step-by-step through the entire process of tracking effective email delivery.


It makes checking email deliverability a breeze


The plugin offers a straightforward and user-friendly experience. Following the simple instructions in the settings page, I successfully added the TXT record to my DNS and my emails were successfully signed. I particularly appreciate the delivery chart and the dashboard, which provide valuable insights on my email deliveries and how to enhance it. These features empower me to ensure a safer and more reliable communication to my customers.


A standout plugin


Unfortunate I do not recieve any email for verifications my account. Tried on different installations and different emails.


Cant make account

Check and improve your Email Deliverability. Pass DMARC by DKIM-signing your emails without an external SMTP. Comply with Google & Yahoo requirements!

SignEmail SMTP & DNS Diagnostic vs Deliverability – pass DKIM, SPF, DMARC & more