Verifying Googlebot and other Google crawlers
You can verify if a web crawler accessing your server really is a Google crawler, such as Googlebot. This is useful if you're concerned that spammers or other troublemakers are accessing your site while claiming to be Googlebot.
There are two methods for verifying Google's crawlers:
- Manually: For one-off lookups, use command line tools. This method is sufficient for most use cases.
- Automatically: For large scale lookups, use an automatic solution to match a crawler's IP address against the list of published Googlebot IP addresses.
Use command line tools
-
Run a reverse DNS lookup on the accessing IP address from your logs, using the
host
command. -
Verify that the domain name is either
googlebot.com
orgoogle.com
. -
Run a forward DNS lookup on the domain name retrieved in step 1 using the
host
command on the retrieved domain name. - Verify that it's the same as the original accessing IP address from your logs.
Example 1:
host 66.249.66.1
1.66.249.66.in-addr.arpa domain name pointer crawl-66-249-66-1.googlebot.com.host crawl-66-249-66-1.googlebot.com
crawl-66-249-66-1.googlebot.com has address 66.249.66.1
Example 2:
host 35.247.243.240
240.243.247.35.in-addr.arpa domain name pointer geo-crawl-35-247-243-240.geo.googlebot.com.host geo-crawl-35-247-243-240.geo.googlebot.com
geo-crawl-35-247-243-240.geo.googlebot.com has address 35.247.243.240
Example 3:
host 66.249.90.77
77.90.249.66.in-addr.arpa domain name pointer rate-limited-proxy-66-249-90-77.google.com.host rate-limited-proxy-66-249-90-77.google.com
rate-limited-proxy-66-249-90-77.google.com has address 66.249.90.77
Use automatic solutions
Alternatively, you can identify Googlebot by IP address by matching the crawler's IP address to the list of Googlebot IP addresses. For other Google IP addresses from where your site may be accessed (for example, by user request or Apps Scripts), match the accessing IP address against the list of Google IP addresses. Note that the IP addresses in the JSON files are represented in CIDR format.