Claude-Web user agent
Operated by Anthropic
Claude-Web is an older, undocumented user agent associated with Anthropic.
The Claude-Web bot at a glance
- Claude-Web is operated by Anthropic and fetches a page when a person asks an AI assistant about it or shares its link.
- The robots.txt token for Claude-Web is Claude-Web.
- Blocking an AI assistant fetcher has no effect on search rankings.
- Claude-Web robots.txt support: Not documented.
- Recommendation for Generative Engine Optimization (GEO): Your choice.
What is Claude-Web?
Claude-Web was seen in server logs before Anthropic documented Claude-User and Claude-SearchBot. Anthropic does not describe it on its current crawler page.
Rules for Claude-User and Claude-SearchBot now control how Claude reads and searches a website.
Should you block Claude-Web?
Blocking Claude-Web is a business decision: it protects your content but can lower how well AI products know your brand.
| Effect on search rankings | Blocking an AI assistant fetcher has no effect on search rankings. |
|---|---|
| Effect on AI visibility | Blocking stops the assistant from reading your page when a user asks about it or pastes your link, so its answer falls back to other sources. |
| Follows robots.txt | Not documented |
| Recommendation | Your choice |
How to block or allow Claude-Web
Put the robots.txt rule in the file at the root of every domain and subdomain, for example https://example.com/robots.txt. The token Claude-Web is matched case-insensitively. robots.txt alone may not stop Claude-Web, so add the Nginx, Apache or Cloudflare rule as well.
robots.txt: block
# Block Claude-Web
User-agent: Claude-Web
Disallow: /robots.txt: allow
# Allow Claude-Web
User-agent: Claude-Web
Allow: /robots.txt: partial
# Keep Claude-Web out of private areas only
User-agent: Claude-Web
Disallow: /wp-admin/
Disallow: /cart/
Disallow: /checkout/
Disallow: /my-account/
Allow: /Nginx
# Nginx: return 403 to Claude-Web
if ($http_user_agent ~* "(Claude\-Web)") {
return 403;
}Apache
# Apache .htaccess: return 403 to Claude-Web
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} (Claude\-Web) [NC]
RewriteRule .* - [F,L]Cloudflare WAF
# Cloudflare > Security > WAF > Custom rule, action: Block
(http.user_agent contains "Claude-Web")How to verify real Claude-Web traffic
Anthropic publishes no IP list or reverse DNS pattern for Claude-Web, so the user agent cannot be verified. Anyone can send the same string. Rate-limit unusual volume instead of trusting the name.
How to find Claude-Web in your server logs
Search the web server access log for the token. The command below counts Claude-Web requests per URL on Nginx or Apache.
grep -i "Claude-Web" access.log | awk '{print $7}' | sort | uniq -c | sort -rn | head -20For a full report per AI bot, upload the log to the AI Log File Analyzer, a free tool by Justin Hà.
Claude-Web FAQ
Claude-Web uses the robots.txt token "Claude-Web". Anthropic does not publish a full user-agent string, so match the token inside the User-Agent header.
Anthropic has not documented how Claude-Web treats robots.txt. Add a robots.txt rule and back it with a server rule if the traffic matters to you.
Blocking an AI assistant fetcher has no effect on search rankings. Blocking stops the assistant from reading your page when a user asks about it or pastes your link, so its answer falls back to other sources.
Add two lines to the robots.txt file at the root of each domain and subdomain: "User-agent: Claude-Web" followed by "Disallow: /". The token is case-insensitive. Changes can take up to 24 hours to be picked up.
Not reliably. Anthropic publishes no IP list or reverse DNS pattern for Claude-Web, so anyone can send the same user agent. Rate-limit unusual volume instead of trusting the name.
Search your server access log for "Claude-Web", for example with: grep -i "Claude-Web" access.log. The AI Log File Analyzer by Justin Hà counts visits per AI bot from an uploaded log file.
Sources: Public bot registry. Last reviewed by Justin Hà.
See which of these bots actually reach your website
The AI Log File Analyzer by Justin Hà counts visits from GPTBot, ClaudeBot, PerplexityBot and other AI crawlers in your server log, for free. The GEO Technical Package sets up robots.txt, llms.txt and crawler access for AI search.
