What tools check PTR records?

PTR/reverse DNS checking:

MXToolbox Reverse Lookup: mxtoolbox.com/ReverseLookup.aspx - PTR lookup and FCrDNS verification.

DNS Checker PTR: dnschecker.org/ptr-lookup.php - global PTR checking.

Command line:

dig -x 192.0.2.1

Then verify: dig A [returned hostname]

What to verify:

PTR record exists for your sending IP

Hostname is meaningful (not generic/residential)

Forward lookup matches (FCrDNS passes)

Check for all sending IPs, including IPv6 addresses.

Verify your reverse registry entry exists and matches your forward registration.