AI crawler comparison
ClaudeBot vs CCBot: what's the difference?
Anthropic's own crawler versus the open dataset that also feeds model training.
Short answer
ClaudeBot and CCBot do the same job — AI model training — so the choice between them is not either/or. If you want to opt out of that use entirely, you need a rule for each of them; blocking one leaves the other free to crawl.
Side by side
| ClaudeBot | CCBot | |
|---|---|---|
| Operator | Anthropic | Common Crawl |
| Purpose | AI model training | AI model training |
| robots.txt | Respects robots.txt | Respects robots.txt |
| Published IP ranges | None published | None published |
| Official docs | Yes | Yes |
| Blocking costs you | No traffic — training only | No traffic — training only |
What ClaudeBot does
ClaudeBot is Anthropic's primary web crawler, collecting publicly available content that may be used to train the Claude family of models. It is the Anthropic equivalent of OpenAI's GPTBot, and the user agent to target if you want to opt out of Claude training specifically.
Full profile, with every robots.txt, nginx, Apache and Cloudflare rule: ClaudeBot.
What CCBot does
CCBot builds Common Crawl, the open web archive that has served as foundational training data for many large language models, including early GPT models. Blocking CCBot is the single broadest AI-training opt-out available, since dozens of model builders consume the Common Crawl dataset downstream.
Full profile, with every robots.txt, nginx, Apache and Cloudflare rule: CCBot.
Block both
User-agent: ClaudeBot Disallow: / User-agent: CCBot Disallow: /
Block ClaudeBot, allow CCBot
The split most sites want when the two agents do different jobs: opt out of one without giving up the other.
User-agent: ClaudeBot Disallow: / User-agent: CCBot Allow: /
Check your own site
- AI Crawler Access Checker — see which of the two your live robots.txt currently allows.
- robots.txt Generator for AI Bots — build per-bot rules for both agents and the other 26.
- AI Bot Log Analyzer — paste your access log and see which of them is actually visiting.
- Should you block AI bots? — the decision framework behind the split above.
Frequently asked questions
What is the difference between ClaudeBot and CCBot?
Both are AI model training agents, but they belong to different operators — ClaudeBot to Anthropic, CCBot to Common Crawl. ClaudeBot: Crawls content to train Anthropic's Claude models. CCBot: Common Crawl's crawler; its dataset is widely used to train LLMs.
Does blocking ClaudeBot also block CCBot?
No. robots.txt matches on the user-agent token, so a group naming ClaudeBot applies only to ClaudeBot. CCBot reads the group that names it, or the wildcard group if none does. To stop both you need a rule for each — or a wildcard rule, which would also affect every other crawler that reads it.
Should I block ClaudeBot, CCBot, or both?
It depends which outcome you want. Blocking ClaudeBot opts you out of Anthropic's model training and costs you no traffic today, because training crawlers send no visitors. Blocking CCBot opts you out of Common Crawl's training data on the same terms. The common choice is to block training agents and allow search agents, so your content stays citable without feeding model training.
Do ClaudeBot and CCBot both respect robots.txt?
ClaudeBot: Anthropic documents ClaudeBot and states it respects robots.txt directives and anti-circumvention signals. CCBot: Common Crawl is a nonprofit with a long public record of honoring robots.txt and crawl-delay directives.
Can I tell ClaudeBot and CCBot apart in my server logs?
Yes — they send different user-agent strings, so grep for each token separately: grep -i "ClaudeBot" and grep -i "CCBot". Be aware that a user-agent header is self-declared and anything can send either string. Neither operator publishes IP ranges for these agents, so log entries claiming them cannot be verified.
Other comparisons
Part of our directory of every known AI crawler. Last verified: 2026-08-14.