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Reverse DNS Lookup

Look up the PTR record behind an IP address, then check whether that hostname resolves back to the same address — the forward-confirmed check mail servers actually apply.

About

A reverse DNS lookup asks the opposite question to a normal one: given an address, what name does it claim? For mail servers it matters because most receivers check that the name a sending IP announces resolves back to the same address. This tool does both halves of that check, showing the PTR record and the forward lookup result side by side.

How to use

  1. Enter an IPv4 or IPv6 address such as 8.8.8.8.
  2. Submit the form to see any PTR records published for it.
  3. Read the verdict: a name that resolves back to the same address passes the forward-confirmed check.

Frequently asked questions

What is a PTR record?

A pointer record that maps an address back to a hostname. It lives in a special zone built from the address itself, which is why the tool also shows the name being queried.

Why does my PTR say something unrelated?

The PTR belongs to whoever owns the IP block, not to you. Broadband and cloud providers often set a generic name such as a pool address, and you may need to request a change from them.

What does forward-confirmed mean?

The PTR name, when looked up forwards, returns the original address. Without that confirmation the PTR counts for very little, and some receivers treat it as a negative signal.