tmailrDeliverability · Observed
Test an email
Send a message to the address below. We report exactly what our mail server observed when it arrived: authentication results, transport security and message structure. This is not a prediction of where a provider will file your mail.
We give you a one-time address. Send a message to it from the setup you want to check, and read back exactly what our server saw.
What this checks
What an email deliverability test actually measures
Whether your email reaches the inbox comes down to a handful of records the receiving server checks the moment your message arrives. This test reads them back exactly as our server saw them, so you can fix what keeps good mail out of the inbox instead of guessing.
SPF
Says which servers are allowed to send mail for your domain. If the sending server is not on that list, receivers treat the message as suspicious. A missing or over-long SPF record is one of the most common reasons legitimate email lands in spam.
DKIM
A cryptographic signature that proves the message was not changed in transit and really came from your domain. Receivers check it against a public key in your DNS; if the signature fails, trust drops fast.
DMARC
Ties SPF and DKIM together and tells receivers what to do with mail that fails both. Without a DMARC policy, anyone can send email pretending to be you, and you never find out it happened.
Alignment
SPF and DKIM only help deliverability if the domain they pass for matches the address in your From header. Alignment is what DMARC actually enforces, and it is the piece most senders miss.
TLS and reverse DNS
Transport security keeps the message encrypted between servers, and a matching reverse-DNS record on the sending IP is a basic sign of a well-run mail server. Missing either one costs reputation with strict receivers like Gmail and Outlook.
Questions people actually ask
Straight answers
Why is my email going to spam even though it looks fine?
Almost always authentication, not content. If SPF, DKIM or DMARC fail or do not align, filters discount the message before they read a word of it. Run the test, fix the failing check, and most "going to spam" problems go with it.
SPF, DKIM or DMARC, which do I actually need?
All three. SPF and DKIM each prove one thing; DMARC makes receivers act on them and reports who is sending as you. Publishing DMARC, even at p=none to start, is the single biggest step for email authentication.
Does passing this test mean I will always reach the inbox?
No, and we will not pretend otherwise. This shows what the receiving server observed: authentication, transport and structure. Inbox placement also depends on your sending reputation and how people engage with your mail. Passing removes the technical reasons to filter you, which is the part you control.
How often should I test my email deliverability?
After any change to how you send, a new provider, a new domain, an edited SPF record, and then every so often. Records drift, includes change, and a setup that passed last month can quietly break.