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Rank 343 in the Majestic Million · checked October 19, 2026

Does yale.edu block AI crawlers?

Partly. As of October 19, 2026, yale.edu'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. None of them is named in the file: they all follow its rules for every crawler (User-agent: *).

It has no llms.txt (HTTP 404). Its homepage is 25,681 tokens of raw HTML, 97 as Markdown (0.4%) and 97 pruned for the question “What is yale.edu?”.

Each crawler, by its robots.txt rules

From https://www.yale.edu/robots.txt (2,491 bytes, 1 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.

CrawlerOperatorVerdictRules that applyDisallow rulesAllow rules
GPTBotOpenAIPartly blockedRules for all crawlers (*)4334
ChatGPT-UserOpenAIPartly blockedRules for all crawlers (*)4334
OAI-SearchBotOpenAIPartly blockedRules for all crawlers (*)4334
ClaudeBotAnthropicPartly blockedRules for all crawlers (*)4334
Claude-UserAnthropicPartly blockedRules for all crawlers (*)4334
Claude-SearchBotAnthropicPartly blockedRules for all crawlers (*)4334
anthropic-aiAnthropicPartly blockedRules for all crawlers (*)4334
PerplexityBotPerplexityPartly blockedRules for all crawlers (*)4334
Perplexity-UserPerplexityPartly blockedRules for all crawlers (*)4334
Google-ExtendedGooglePartly blockedRules for all crawlers (*)4334
Applebot-ExtendedApplePartly blockedRules for all crawlers (*)4334
CCBotCommon CrawlPartly blockedRules for all crawlers (*)4334
BytespiderByteDancePartly blockedRules for all crawlers (*)4334
AmazonbotAmazonPartly blockedRules for all crawlers (*)4334
meta-externalagentMetaPartly blockedRules for all crawlers (*)4334
cohere-aiCoherePartly blockedRules for all crawlers (*)4334
DiffbotDiffbotPartly blockedRules for all crawlers (*)4334
ContextFetchBot (us)ContextFetchPartly blockedRules for all crawlers (*)4334
Checked October 19, 2026 by ContextFetchBot. Google-Extended and Applebot-Extended are robots.txt tokens that control use of content for AI, not separate crawlers.

Its homepage in tokens

https://www.yale.edu/, 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.

Tokens of the yale.edu homepage as raw HTML, Markdown and pruned context, October 19, 2026
GroupRaw HTMLMarkdownPruned
Tokens25,6819797

Read yale.edu 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. yale.edu'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://www.yale.edu/"

How 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.