Is your SMTP actually delivering?
Send a real message to our mailbox the same way you'd send to a subscriber. We'll show you whether it arrived — and where.
Free SMTP Tester & Mail Server Checker
- What does an SMTP test check?
- It confirms your mail server accepts connections, authenticates correctly, and can actually deliver mail — the plumbing that has to work before deliverability matters.
- Is this the same as checking deliverability?
- Not quite. SMTP testing checks that your server can send; deliverability checks whether what you send lands in the inbox. Mailtester focuses on the second — where your campaign actually ends up.
- How do I test my SMTP setup?
- Forward an email through your server to your Mailtester address. We read the delivery path from the real message and flag any connectivity or authentication problems.
€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.