# CCBot

> Common Crawl's corpus builder. It trains nothing itself, but its archive is an input to most open and many closed LLM training sets, which makes it the highest-leverage single entry on this list.

| field | value |
|---|---|
| operator | Common Crawl |
| category | Corpus and dataset builders |
| robots.txt token | `CCBot` |
| user-agent contains | `CCBot` |
| robots.txt | obeys robots.txt (documented) |
| verify by | no published verification method |
| published IP ranges | none published |
| prefixes mirrored | 0 IPv4 / 0 IPv6 |
| operator docs | https://commoncrawl.org/faq |
| last reviewed | 2026-09-01 |

## What blocking it costs you

Future Common Crawl snapshots exclude you, so downstream training sets lose you too — but only going forward. Existing snapshots are permanent and blocking today does not retract them.

## Full user-agent string

```
CCBot/2.0 (https://commoncrawl.org/faq/)
```

## Block it

```
User-agent: CCBot
Disallow: /
```

## Allow it

```
User-agent: CCBot
Allow: /
```

JSON: https://www.pathwren.workers.dev/crawler/ccbot.json · index: https://www.pathwren.workers.dev/llms.txt