How to use this tool
Displays only MX records, then inspects up to five mail servers for priority, addresses, aliases, reverse DNS and TCP port 25 connectivity. No email is sent. A blocked port does not prove the remote server is broken.
Enter the target, complete any relevant options and choose Check. Review the requested records, query outcomes and diagnostic findings. Copy Report saves the visible report.
Reading the results
No matching records and an unavailable query are different outcomes. TTLs are displayed in seconds; zero is a valid TTL. A completed request does not mean a domain passed its health checks. Only the submitted DNS owner and explicitly listed checks are inspected.
Frequently Asked Questions
Does this checker display MX priority?
No. The visible table has no priority field, even though the server record mapping retains a priority value internally.
Does it test SMTP connectivity?
No. The code does not open an SMTP connection or report a port, banner, or response.
Does the page check reverse DNS for mail servers?
No. It does not take the returned MX hosts through a reverse address lookup.
Why are records other than MX visible?
The implementation requests general DNS data rather than limiting the query to MX.
Can a listed mail host guarantee successful delivery?
No. DNS publication alone does not verify server availability, recipient handling, authentication, or reputation.
Why does an old mail host still appear?
The recursive resolver may keep the earlier MX answer until its TTL expires.