How to Verify Googlebot IP Addresses with Reverse DNS

If your logs show an IP like 66.249.64.226 with a hostname such as crawl-66-249-64-226.googlebot.com, the right question is simple: is this really Googlebot, or is someone pretending?

Do not decide from the user agent alone. User agents are easy to fake.

The safer check is reverse DNS plus forward DNS.

Quick answer for 66.249.64.226

On May 3, 2026, this local check resolved cleanly:

host 66.249.64.226

226.64.249.66.in-addr.arpa domain name pointer crawl-66-249-64-226.googlebot.com.

Then the hostname resolved back to the same IP:

host crawl-66-249-64-226.googlebot.com

crawl-66-249-64-226.googlebot.com has address 66.249.64.226

That is the pattern you want: the IP points to a Googlebot hostname, and the hostname points back to the same IP.

How Google says to verify Googlebot

Google's crawler verification guidance gives two practical options:

• run a reverse DNS lookup on the source IP, then run a forward DNS lookup on the returned hostname
• compare the source IP against Google's published crawler IP ranges

For normal server-log checks, the reverse-plus-forward DNS method is usually fast enough.

Google's common crawler hostname pattern includes names like:

crawl-***-***-***-***.googlebot.com
geo-crawl-***-***-***-***.geo.googlebot.com

Official references:

• Googlebot and other Google crawler verification
• What is Googlebot?

The reverse DNS workflow

Start with the IP from your server log.

Run:

host 66.249.64.226

Check whether the returned hostname ends with an expected Google crawler domain such as googlebot.com, google.com, or googleusercontent.com.

Then run a forward lookup on that hostname:

host crawl-66-249-64-226.googlebot.com

If the forward lookup returns the original IP, the result is much stronger.

Why the forward lookup matters

Reverse DNS alone is not enough.

A reverse hostname can look plausible while still being stale, misleading, or unrelated to the current requester. The forward lookup closes the loop. It checks whether the hostname maps back to the same address you started with.

This is often called forward-confirmed reverse DNS.

What to do with the result

If the reverse and forward checks match, treat the request as likely Googlebot and debug it like a crawler request:

• review robots.txt
• check status codes
• inspect crawl timing
• check whether the requested URL should exist
• avoid blocking it just because the request looks automated

If the hostname does not match, or the forward lookup does not return the original IP, treat it as unverified. A bot can say Googlebot in the user agent without being Googlebot.

Where IP lookup fits

Use IP Address Lookup or IP Location for broad context such as ASN, network owner, and location. Use reverse DNS and forward DNS for the crawler identity check.

They answer different questions.

IP lookup helps explain the network. DNS verification helps confirm whether the crawler identity is believable.

FAQ

Is 66.249.64.226 Googlebot?

A local reverse and forward DNS check on May 3, 2026 matched 66.249.64.226 to crawl-66-249-64-226.googlebot.com and back to the same IP. That is the expected verification pattern.

Can a user agent prove a request is Googlebot?

No. User agents can be spoofed. Use reverse DNS plus forward DNS, or compare the source IP against Google's published crawler IP ranges.

Should I block fake Googlebot traffic?

If a request claims to be Googlebot but fails verification, treat it like any other untrusted automated traffic. Check logs, rate, requested paths, and security rules before deciding what to block.

Does an IP location map prove a crawler is Googlebot?

No. Location and ASN are supporting context. Googlebot verification depends on DNS verification or published IP ranges.