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Sender check for your domain
Enter your domain. We check SPF, DKIM, DMARC and the inbox (MX) and explain in plain words what is missing, including the rules Gmail and Yahoo set for bulk senders in 2024.
We do not store the domain you check. The result reflects public DNS right now and is no guarantee of delivery.
What we check
We query the public DNS of your domain, just like a mailbox provider does when it receives your email.
- SPF: exactly one record, a sensible ending (~all or -all), and fewer than 10 DNS lookups?
- DKIM: is there a key under the common selectors? You can enter your service's own selector.
- DMARC: a valid record at _dmarc, which policy applies, and do reports arrive?
- MX: does the domain have an inbox for replies?
The Gmail and Yahoo rules
According to Google, senders of more than 5,000 messages a day to Gmail accounts need SPF and DKIM, a DMARC record with at least p=none, a From address aligned with SPF or DKIM, one click unsubscribe and a low spam rate. Yahoo has similar rules. Smaller senders benefit too.
Why DKIM is sometimes not found
DKIM keys live under a selector your email service chooses. Many services, such as Amazon SES, use random names that cannot be guessed from outside. If the check finds nothing, DKIM may still be in place. A test email to yourself shows dkim=pass in the headers.
Frequently asked questions
Do you store my domain?
No. We query DNS, show the result and store nothing. To prevent abuse we limit the number of checks per minute.
I just added a record and it is not found.
DNS changes take time to show up everywhere, sometimes a few hours. Check again later.
Does a green result mean I reach the inbox?
The records are the foundation. Inbox placement also depends on content, list quality, complaints and sender reputation. A green result is no guarantee.
Not legal advice. These notes do not replace a review by a lawyer.