CCBot
Builds Common Crawl's open repository of web crawl data, which researchers and AI labs download; many models have been trained on it. Blocking it keeps future snapshots from including the site.
Where this comes from
- Documented by the vendor. Source: commoncrawl.org
- Honours robots.txt.
- Listed, not scored. It cannot keep a site out of today's answers, so the check shows a block without deducting for it.
In the top 1,000 websites
- 20.9% block it in robots.txt (119 of the 569 sites with a robots.txt), as of 2026-10-12.
- Method, limits and the full data: the October 2026 study of the top 1,000 websites.
What blocking it costs
Nothing in today's answers, and nothing in the readiness score: CCBot only gathers training data, so blocking it is a policy choice about future models, not about being found. The check lists the block without deducting for it.
The robots.txt lines
To let it in (a group that names the crawler replaces any wildcard rules for it, so this also lifts a User-agent: * block):
User-agent: CCBot
Allow: /To keep it out:
User-agent: CCBot
Disallow: /A rule in robots.txt is a request. Common Crawl says this crawler honours it. The robots.txt generator writes a whole file with the same split: block the training crawlers, keep the search and answer crawlers.
Does CCBot get through on your site?
Run the free check: it reads your robots.txt against all 51 crawlers and tells you which ones can read you, and what to change.