Rank 286 in the Majestic Million · checked October 19, 2026
Does ubuntu.com block AI crawlers?
Partly. As of October 19, 2026, ubuntu.com's robots.txt blocks none of the 17 AI crawlers we check from the whole site, but keeps all 17 out of parts of it. 13 of them are named in a group of their own; the others follow its rules for every crawler.
It serves an llms.txt (12,879 bytes, starting with a Markdown title). Its homepage is 52,429 tokens of raw HTML, 614 as Markdown (1.2%) and 109 pruned for the question “What is ubuntu.com?”.
Each crawler, by its robots.txt rules
From https://ubuntu.com/robots.txt (5,511 bytes, 2 user-agent groups), parsed per RFC 9309. Blocked: no path allowed. Partly blocked: some paths disallowed. The rule counts are those of the groups that apply.
| Crawler | Operator | Verdict | Rules that apply | Disallow rules | Allow rules |
|---|---|---|---|---|---|
| GPTBot | OpenAI | Partly blocked | Its own group | 71 | 46 |
| ChatGPT-User | OpenAI | Partly blocked | Its own group | 71 | 46 |
| OAI-SearchBot | OpenAI | Partly blocked | Its own group | 71 | 46 |
| ClaudeBot | Anthropic | Partly blocked | Its own group | 71 | 46 |
| Claude-User | Anthropic | Partly blocked | Rules for all crawlers (*) | 46 | 0 |
| Claude-SearchBot | Anthropic | Partly blocked | Its own group | 71 | 46 |
| anthropic-ai | Anthropic | Partly blocked | Its own group | 71 | 46 |
| PerplexityBot | Perplexity | Partly blocked | Its own group | 71 | 46 |
| Perplexity-User | Perplexity | Partly blocked | Its own group | 71 | 46 |
| Google-Extended | Partly blocked | Its own group | 71 | 46 | |
| Applebot-Extended | Apple | Partly blocked | Its own group | 71 | 46 |
| CCBot | Common Crawl | Partly blocked | Rules for all crawlers (*) | 46 | 0 |
| Bytespider | ByteDance | Partly blocked | Its own group | 71 | 46 |
| Amazonbot | Amazon | Partly blocked | Rules for all crawlers (*) | 46 | 0 |
| meta-externalagent | Meta | Partly blocked | Its own group | 71 | 46 |
| cohere-ai | Cohere | Partly blocked | Its own group | 71 | 46 |
| Diffbot | Diffbot | Partly blocked | Rules for all crawlers (*) | 46 | 0 |
| ContextFetchBot (us) | ContextFetch | Partly blocked | Rules for all crawlers (*) | 46 | 0 |
Its homepage in tokens
https://ubuntu.com/, fetched once and converted locally with the ContextFetch engine. Tokens are characters divided by four, rounded up, the count the API reports in its X-Raw-Tokens and X-Output-Tokens headers.
| Group | Raw HTML | Markdown | Pruned |
|---|---|---|---|
| Tokens | 52,429 | 614 | 109 |
Read ubuntu.com through ContextFetch
GET /r/ returns a page as Markdown, with X-Raw-Tokens and X-Output-Tokens headers. Add ?q= and a question to get only the passages that answer it. No key needed for 25 requests a day; a free key has 2,500 credits. ubuntu.com's robots.txt partly blocks ContextFetchBot: our index and crawls skip what it disallows, and a page you ask for is fetched once on your behalf (see the bot page).
curl -si "https://api.contextfetch.dev/r/https://ubuntu.com/"curl -X POST https://api.contextfetch.dev/v1/keys/freeHow ContextFetchBot behaves · All sites and the method · Raw data
Give your agent the web
Your free key comes with 2,500 credits, no signup. One credit reads one page.