Reverse DNS for Mail Servers
Receiving mail servers check that a sender's IP has a PTR record that matches its name. Check yours below.
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Examples:
Reverse DNS Lookup
What a mail server's reverse DNS needs
PTR Recordmail.example.com
Forward Recordmail.example.com → the same IP
SMTP Greeting (HELO)mail.example.com
Who Sets ItYour hosting provider or ISP
Gmail requires every sending IP to have a PTR record whose name resolves back to the same IP (forward-confirmed reverse DNS). Without it, mail is rejected or sent to spam.
Use one name everywhere: the PTR, the A record and the name the server gives in its SMTP greeting. Generic provider names such as 203-0-113-25.static.example.net work but look like a home connection to filters.
Reverse DNS Guides
Questions
Does Gmail check reverse DNS?
Yes. Google's sender guidelines require a valid PTR record that resolves back to the sending IP.
How do I set reverse DNS?
In your hosting provider's control panel (often under the IP or network settings), or by asking their support. Your domain's DNS provider cannot set it.
Free Tools
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Reverse DNS LookupPTR record for an IP, and whether it is forward-confirmed.DNS LookupA, AAAA, MX, NS, TXT, CNAME, SOA and CAA records for any domain.SPF CheckerValidate an SPF record and count its DNS lookups against the limit of 10.IP Reputation CheckerCheck an IP against spam blocklists and threat feeds at once.
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