What is Netcraft?
Netcraft is a web crawler that conducts comprehensive internet surveys, analyzing web server technologies and infrastructure across millions of websites to provide market intelligence. You can set up Agent Analytics to see when Netcraft visits your website.
Category
| Example User Agent | Mozilla/4.0 (compatible; Netcraft Web Server Survey) |
| Operated By | Netcraft |
| Source | Official Website |
| Triggered By | Operator-configured crawl |
| Used for AI Model Training | Possibly |
| Affects AI Chat & Search Visibility | Not directly |
| Expected To Follow Robots.txt | Yes |
Why Is Netcraft Visiting My Website?
Netcraft or one of its clients may be gathering competitive intelligence, measuring advertisements, or evaluating content for brand safety. The pages requested reflect the underlying objective.
Should I Block Netcraft?
Confirm Netcraft's purpose before blocking it. Intelligence gatherers may collect competitive research, measure advertisements, or evaluate pages for brand safety. Weigh any benefit against sharing business or page-level data with its operator or clients. For context, 7% of the top websites we track currently have robots.txt rules for Netcraft.
How Do I Block Netcraft Using Robots.txt?
Add this rule to your robots.txt file to block Netcraft from accessing your website, or use Automatic Robots.txt to block all intelligence gatherers at once. You can customize which pages are blocked by swapping out / for a different path.
User-agent: Netcraft # https://knownagents.com/agents/netcraft
Disallow: /Insights for Netcraft
As of October 29, 2026, this data reflects agent visits measured across thousands of websites using Agent Analytics, combined with daily scans of the top 1000 websites and their robots.txt files.
Robots.txt Compliance
Country of Origin
Robots.txt Blocked Percentage
Netcraft Traffic
Frequently Asked Questions
What Traffic Patterns Should I Expect From Netcraft?
Netcraft's traffic pattern depends on the intelligence being collected. It may revisit specific pages on a schedule, crawl broader sections of your site, or appear only when information is requested. Its request scope and frequency reflect the underlying objective.
Does Netcraft Follow Robots.txt Rules?
Netcraft is expected to follow robots.txt rules, so a disallow rule is the appropriate first step if you want to block it. Automatic Robots.txt can add and maintain that rule, while Agent Analytics lets you verify whether Netcraft respects it.
Is Netcraft Used for AI Model Training?
Possibly, but its category does not establish that purpose. Netcraft's operator may use or provide the collected content for AI training or for unrelated automated tasks.
Does Blocking Netcraft Affect AI Search or Citations?
Not directly. Netcraft's expected purpose is not to supply an AI search index or retrieve pages for AI-generated answers.
Does Netcraft Access Private Content?
No special access. Netcraft can read publicly available pages but cannot bypass authentication. Assume anything you publish openly may be collected.
How Can I Verify a Request From Netcraft?
Agent Analytics tracks Netcraft visits in real time. You can also check your server logs for requests whose user-agent string contains "Netcraft". Traffic may range from repeated requests to the same pages to broader crawls or one-off fetches. Because Netcraft does not publish a verification method, any client can claim its identity and a log match is only a clue.
How Is Netcraft Different From Other Netcraft Agents?
Netcraft operates separate agents for different purposes, so each agent should be evaluated and controlled independently.
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