ClaudeBot vs PerplexityBot: Which AI Crawler Should You Allow or Block?

Mistakes when writing rules for ClaudeBot and PerplexityBot together

ClaudeBot is named in 15.4% of the top-site robots.txt files in our study and blocked in 14.4%; PerplexityBot is named in 12.9% of the top-site robots.txt files in our study and blocked in 10.9%. Large sites block ClaudeBot more often, which usually reflects a decision about training rather than about PerplexityBot.

1. They are different kinds of agent (a training crawler versus a retrieval crawler that feeds AI search answers), so the usual error is giving them the same rule out of habit. Blocking both to stop training only needs the ClaudeBot line; the other one changes something else entirely.
2. They come from different operators (Anthropic and Perplexity AI), with different documentation and different update cycles. Do not assume a change one of them announces applies to the other.
3. Putting User-agent: ClaudeBot and User-agent: PerplexityBot in separate groups and then editing only one. Two groups drift apart over time; keep a comment above each that says why it differs from the other.

Each crawler's own profile lists the mistakes that apply to it alone; this list is only about combining the two.

Spotting ClaudeBot and PerplexityBot in your logs

robots.txt says what ClaudeBot and PerplexityBot may do; your access logs show what they actually did.

Count requests

On a server with standard Nginx or Apache logs, this counts matching requests per day (adjust the log path for your host):

grep -iE "ClaudeBot|PerplexityBot" /var/log/nginx/access.log \
  | awk '{print $4}' | cut -d: -f1 | sort | uniq -c

And this shows which paths it requested most, which is the quickest way to see whether your Disallow lines are being respected:

grep -iE "ClaudeBot|PerplexityBot" /var/log/nginx/access.log \
  | awk '{print $7}' | sort | uniq -c | sort -rn | head -20

Check the requests are genuine

Anyone can send these user-agents, so confirm the source before acting on a match:

• ClaudeBot: compare each address with the ranges at claude.com/crawling/bots.json. A request claiming to be ClaudeBot from outside them is not genuine. Check it separately from PerplexityBot.
• PerplexityBot: compare each address with the ranges at www.perplexity.com/perplexitybot.json. A request claiming to be PerplexityBot from outside them is not genuine. Check it separately from ClaudeBot.

How ClaudeBot and PerplexityBot moved in our latest scans

Between our scans of October 17, 2026 and October 20, 2026, files naming ClaudeBot went from 800 to 858 (+58) and files blocking it from 745 to 805 (+60), so more sites wrote a rule for ClaudeBot and more of those rules block it. For comparison, 2026 and October 20, 2026, files naming PerplexityBot went from 693 to 718 (+25) and files blocking it from 582 to 609 (+27), so more sites wrote a rule for PerplexityBot and more of those rules block it.

Related: writing content AI engines can cite

Over the 3 days between those scans, blocking of ClaudeBot moved +60 files and blocking of PerplexityBot moved +27. Owners are acting faster on ClaudeBot, which is the one to recheck first if you have not touched your file this month.

We first recorded ClaudeBot on March 17, 2026. Anthropic documents it on support.claude.com, and we recheck that page before each release. We first recorded PerplexityBot on March 17, 2026. Perplexity AI documents it on docs.perplexity.ai, and we recheck that page before each release.

Among the 104 AI and LLM crawlers in our database, ClaudeBot sits seventh by priority (Tier 1), level with ChatGPT Agent, ChatGPT Operator, ChatGPT-User, ChatGPT-User/2.0. 81 of the 104 share its safe rating. On the PerplexityBot side: Among the 104 AI and LLM crawlers in our database, PerplexityBot sits 14th by priority (Tier 1), level with ChatGPT Agent, ChatGPT Operator, ChatGPT-User, ChatGPT-User/2.0. 81 of the 104 share its safe rating.

How top sites treat ClaudeBot and PerplexityBot

From our robots.txt study of the Tranco top 10,000 (5,583 valid files, fetched October 20, 2026):

• ClaudeBot, the most blocked of the ClaudeBot and PerplexityBot tokens: blocked in 14.4% of files (594 with its own group, 211 through User-agent: *), more often by the top 1,000 (20.4%) than the long tail (13.3%).
• PerplexityBot, second of the ClaudeBot and PerplexityBot tokens: blocked in 10.9% of files (406 with its own group, 203 through User-agent: *), more often by the top 1,000 (17%) than the long tail (9.3%).

For scale, 20.1% of all files block at least one AI training crawler. ClaudeBot is one of the tokens driving that figure.

More questions about ClaudeBot and PerplexityBot

Can I allow one and block the other?

Yes. Give each its own User-agent group with its own rules. Each crawler reads only the group that names it.

Which of the two visits more often?

It depends on your site, your audience and how often your content changes. Your access logs are the reliable answer; the commands above count both.

How long until a change applies?

Crawlers commonly cache robots.txt for up to a day, so allow about 24 hours and confirm in your logs.

Do I need to update my rules when either operator launches a new crawler?

Often, yes. A new token is not covered by rules written for the old ones. Check this comparison and both profiles periodically, or rerun the AI search crawlability check after any announcement.