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DNS, SSL & email

Email deliverability test

Send a message to a one-off address and we check SPF, DKIM, DMARC, PTR, blacklists, headers and content, and score it out of 10. Free, without a 3-tests-a-day cap.

1. Send a message, the same as you normally send, to this address:

2. Press “Check”: we wait for the message and show the result.

The message is kept for 24 hours, readable only through this address, then deleted.

What is checked

  • SPF, DKIM and DMARC as the receiving server saw them, and your domain records in DNS.
  • The sender IP: reverse DNS (PTR), forward confirmation and 25 blacklists.
  • Headers: Message-ID, Date, List-Unsubscribe for bulk mail, Reply-To to another domain.
  • Content: a plain-text part, URL shorteners, “spammy” words, size.

How to raise the score

  1. Set up SPF and DMARC with the SPF and DMARC generator and turn on DKIM at your mail service.
  2. Ask your host to set a PTR for the mail server IP matching its name.
  3. If the IP is blacklisted, fix the cause and request delisting; blacklist check gives the links.

The whole domain

This tests one message. Who else sends mail as you is shown by DMARC reports.

More tools: dns, ssl & email

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