ClaudeBot
Anthropic Claude web crawler bot
About this crawler
ClaudeBot is a web crawler identified by the regular-expression pattern [cC]laude[bB]ot in the User-Agent request header. It is categorised as ai-crawler. Use the regex above to detect, log, allow, or block ClaudeBot traffic in your web server, CDN edge rules, or robots.txt.
Block-rate · top 25k sites
8.5%
Technical details
- Name
- ClaudeBot
- Pattern
[cC]laude[bB]ot- Tags
- ai-crawler
- Reference
- https://www.anthropic.com/
- Added
- 2024/04/19
- rDNS suffixes
.anthropic.com- Instances
- 2 known sample(s)
rDNS verification (FCrDNS)
Verify a request is genuinely ClaudeBot with forward-confirmed reverse DNS: the client IP's PTR record must end in one of the suffixes below and a forward A/AAAA lookup of that hostname must return the same IP. UA strings alone are spoofable; FCrDNS is not.
.anthropic.com
Sample User-Agent strings
claudebot
Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])
Block this crawler
robots.txt — disallow ClaudeBot:
User-agent: ClaudeBot
Disallow: /
Apache .htaccess — return 403:
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} [cC]laude[bB]ot [NC]
RewriteRule .* - [F,L]
Nginx — return 403 inside a server block:
if ($http_user_agent ~* "[cC]laude[bB]ot") {
return 403;
}
← back to all crawlers