Does your email prove it's really from you?
DKIM is the signature that stops inboxes from quietly demoting you. Forward a real send — we'll show you the result.
Free DKIM Analyzer & Signature Validator
- What is DKIM?
- DKIM (DomainKeys Identified Mail) adds a cryptographic signature to every email you send, so the receiving mailbox can verify the message wasn't altered and really came from your domain.
- Do I need DKIM if I already have SPF?
- Yes — SPF and DKIM check different things, and Gmail, Yahoo, and Outlook increasingly expect both. DMARC, the policy that ties them together, only works when DKIM is in place.
- How do I test my DKIM signature?
- Forward an email to your Mailtester address. We check the DKIM signature on the real message and show you whether it validates — no DNS digging required.
€9.99 for AI deep-dives.
You forward it.
Paste the mailbox above into the test-send field in Beehiiv, Kit, Substack, Mailchimp — or your own inbox. Hit go. We never see your subscriber list.
We actually open it.
In real Gmail, real Outlook, real Yahoo. We watch where your email lands — Primary, Promotions, or Spam — using the same filters that decide whether your campaign worked.
You get a report.
Plain English. Three things to change, in priority order. Unlock the bundle and we generate a subject, body, and CTA rewrite in your voice — paste them back into your campaign before lunch.
Two different tests.
Most people mix them up.
If you've ever searched "email tester," half the results check whether the address is valid. We do the other thing — whether the email itself will reach the inbox once you press send.
You upload a CSV of subscribers. The tool tells you which addresses bounce. Great for cleaning a stale list before a re-engagement send.
You forward one email — newsletter, launch, client note — to a one-time mailbox. We open it in real Gmail, Outlook, and Yahoo and tell you which tab it landed in, plus what to rewrite before you send it to your list.
We check whether your sends will land. That's the whole product.
Free to score. Pay only for the AI deep-dive.
Forward any email and get the score — free and unlimited. Buy credits when you want the occasional AI deep-dive, or go €9.99/mo if you send regularly. Cancel from the same screen you upgrade on.
Send your next one to the inbox.
Takes less time than picking a hero photo. No card, no signup, no anything.