Usually your ISP or hosting provider for the IP block they assigned.

PTR mismatch mail error?

Forward DNS A record should match PTR hostname for mail servers.

Reverse DNS for home IP?

Residential IPs rarely have custom PTR — use SMTP relay for mail.

Yes. IP Checker publishes this guide and Reverse DNS at no cost. No account is required for standard use.

No. Open the guide’s tool link in any modern browser on desktop, tablet, or phone.

This guide explains concepts and keywords in depth. The tool page runs the live check and shows instant results.

We do not permanently store queries from these tools. Some checks run in your browser; others fetch public data for that request only.

Yes. Link to https://ipchecker.online/guides/reverse-dns-guide or the tool at /tools/reverse-dns.

PTR lookup for mail deliverability and troubleshooting

In-depth guide · 8 FAQs · ~1000+ words

Topics: reverse dns · ptr record lookup · ptr record · rdns lookup

DNS Tools

Reverse DNS Lookup

Resolve IP addresses to hostnames via PTR records

A → 93.184.216.34

MX → mail.example.com

TXT → v=spf1 include:_spf...

NS → ns1.example.com