Feeds the Common Crawl open dataset, which many model trainers build on.
| Operating Entity | Common Crawl |
| Primary Purpose | Training / Model Pre-training Crawler |
| Exact User-Agent String | CCBot |
| Robots Control Token | No (active HTTP web crawler) |
| Robots Protocol Status | No (strictly conforms to robots.txt RFC 9309 rules) |
| Official Documentation | https://github.com/ai-robots-txt/ai.robots.txt |
| Cloudflare Edge Default | Blocked by default on ad-supported tiers of newly registered domains since September 15, 2026 under Cloudflare's AI scraper protections. |
| Real Blocking Impact | Blocking CCBot prevents your web pages from entering future Common Crawl snapshots, drastically reducing the chances that open-weights or non-proprietary models train on your content. It does not affect commercial search engines. |
| Related Portfolio Bots | Diffbot, Webzio-Extended, AI2Bot |
CCBot is the automated web crawler operated by Common Crawl, a 501(c)(3) non-profit organization established in 2007. Common Crawl produces open-access datasets of the public web, which serve as foundational pre-training corpora for hundreds of commercial and open-weights AI models, including Meta's Llama, Mistral, and academic initiatives. As artificial intelligence engines transition from closed training runs toward live, real-time knowledge retrieval, understanding the mechanical distinctions between background model pre-training and conversational inference is paramount for modern digital publishers and web engineering teams.
CCBot traverses billions of URLs monthly using distributed cloud clusters hosted on AWS. It reads robots.txt, respects Crawl-delay and Disallow directives, and extracts clean text and WARC archive records for public release. Because CCBot's dataset is open, any AI organization can train on Common Crawl archives. When web servers receive incoming connections from CCBot, the underlying networking stacks evaluate whether the request adheres to documented IP subnets, whether DNS reverse-lookups validate operator provenance, and whether the targeted URLs are cleared by domain governance policies.
Data Processing & Ingestion Architecture: Web pages crawled by CCBot are packaged into open WARC files, published freely on Amazon S3, and ingested by academic researchers, AI startups, and multinational technology conglomerates to pre-train LLMs. For website operators, this architecture dictates whether your intellectual property is processed into static parameters of large language models or referenced dynamically during conversational question-answering sessions.
Cloudflare and Edge Firewall Status: Blocked by default on ad-supported tiers of newly registered domains since September 15, 2026 under Cloudflare's AI scraper protections. On September 15, 2026, Cloudflare introduced foundational changes to its default bot management system across all ad-supported tiers of newly created domains. If your origin server relies entirely on robots.txt files to govern CCBot, you may experience discrepancies where the edge firewall terminates the crawler connection with an HTTP 403 Forbidden code before your origin application or robots.txt parser is even invoked.
Verifying whether CCBot can successfully reach and process your web pages requires looking across three separate, non-overlapping architectural layers: the robots.txt policy layer, the network-level User-Agent HTTP probe layer, and the page-level indexability layer. Assuming that a passing result in one layer guarantees full visibility in another is a widespread engineering trap.
Step 1: Test the User-Agent via HTTP curl emulation
Execute the following command in your terminal to inspect how your web server, CDN, and WAF respond when a client identifies with the CCBot user agent string:
curl -A "CCBot/1.0" -I https://yoursite.com
Analyze the HTTP response headers carefully:
Step 2: Inspect Page-Level Index Directives
Even if CCBot is fully allowed to crawl a URL over HTTP, it cannot index or cite the page if the document carries a noindex directive in its response headers (X-Robots-Tag: noindex) or in its HTML header (<meta name="robots" content="noindex">). A crawlable page can still be completely invisible to search indexes.
Step 3: Run the Free Automated AI Crawler Visibility Check
Instead of manually running command-line probes and inspecting headers across multiple hosts, use our instant free AI crawler visibility checker on checkaibots.com. It simultaneously audits your website against CCBot and 39 other major AI crawlers, compares www versus naked domain robots.txt configurations, performs UA-level HTTP baseline probes, and flags accidental misconfigurations in seconds.
To grant CCBot full permission to crawl your website in accordance with the official RFC 9309 protocol, place an explicit User-agent declaration at the root of your domain (https://yoursite.com/robots.txt).
Standard Full-Site Access Rule:
User-agent: CCBot Allow: /
Selective Access (Protecting Sensitive Subdirectories):
If your website contains private administrative portals, checkout flows, internal search results, or user account dashboards, you can protect those sensitive paths while granting CCBot unrestricted access to public articles, blog posts, documentation, and product catalogs:
User-agent: CCBot Allow: / Disallow: /admin/ Disallow: /checkout/ Disallow: /internal/ Disallow: /api/ Disallow: /*?token=*
RFC 9309 Rules and Precedence: Under official robots.txt protocol rules, when multiple path rules match a given URL, the rule with the longest matching character length takes absolute precedence. In the event of a tie where both an Allow and a Disallow rule have identical string lengths, the Allow directive wins. Furthermore, avoid the common error of leaving an empty Disallow statement (Disallow:), which according to the specification acts as a complete permit for all paths.
If your organization's copyright policy, competitive licensing stance, or infrastructure budget requires restricting CCBot, you can signal an explicit block by adding the following directive to your robots.txt file:
User-agent: CCBot Disallow: /
Crawl Budget and Cache Invalidation: Once your robots.txt file is updated, automated crawlers typically require between 24 and 48 hours to refresh their cached copy of your domain's directives. Existing data already ingested into previously trained neural weights cannot be retroactively purged via robots.txt, but future training iterations and live indexing updates will respect the updated boundary.
A primary failure mode in modern search optimization is treating all crawlers from a given artificial intelligence operator as a monolithic entity. Operators such as OpenAI, Anthropic, Google, and Meta partition their crawling infrastructure into distinct functional categories: bulk model pre-training crawlers, real-time search citation indexers, and user-directed live fetchers.
The table below illustrates the exact architectural distinctions, operational objectives, and visibility implications across Common Crawl's crawler fleet and comparable industry counterparts:
| Crawler Token | Functional Role | Affects Citations? | Affects Training? | Cloudflare Default |
|---|---|---|---|---|
| CCBot (Current) | Training / Model Pre-training Crawler | No | Yes (Directly) | Blocked |
| GPTBot | Training Crawler | No | Yes (Training) | Blocked |
| ClaudeBot | Training Crawler | No | Yes (Training) | Blocked |
| anthropic-ai | Training Crawler | No | Yes (Training) | Blocked |
The Expensive Mistake in AI SEO: When organizations implement blanket robots.txt disallows aiming to protect copyright, they frequently copy-paste blocklists that include both training crawlers and search indexers (such as blocking OAI-SearchBot while intending to block GPTBot). Disallowing a search indexer silently excises the domain from AI answers, preventing brand citations, referral clicks, and audience discovery while leaving model training opt-outs completely unaffected. Keep your training policies and search indexing permissions strictly decoupled.
Blocking CCBot only prevents future inclusion. Past Common Crawl datasets are public and immutable.
Common Crawl is a data repository, not a search engine. Blocking it does not harm Google or Bing rankings.
If CCBot crawls too fast, use Crawl-delay in robots.txt rather than completely disallowing it.
AWS WAF Bot Control can automatically manage CCBot traffic.
Many sites serve completely different robots.txt files on www.yoursite.com and the bare domain yoursite.com. Automated crawlers treat these as separate origins; if you update one host but omit the other, crawlers will continue encountering old directives.
Common Crawl data is utilized across the global AI ecosystem, including Meta (for Llama pre-training), Mistral AI, EleutherAI, AI2 (Dolma), and independent AI researchers.
No. Common Crawl archives are immutable historical snapshots. Blocking CCBot prevents inclusion in future crawl releases but does not retroactively alter past archives.
Yes. Common Crawl documents that CCBot honors the Crawl-delay directive in robots.txt, allowing webmasters to throttle request rates.
Yes. Cloudflare's automated AI Scrape Shield classifies CCBot as an AI Scraper and blocks it at the edge by default on new domains.
Add 'User-agent: CCBot Disallow: /' to your robots.txt file.