AI crawler · DuckDuckGo
DuckAssistBot: what it is and how to block it
DuckAssistBot fetches pages in real time for DuckDuckGo's AI-assisted answers, which cite their sources. DuckDuckGo says blocking it doesn't affect your regular search rankings.
BrandVector Editorial · Last verified Oct 8, 2026
- Operator
- DuckDuckGo
- Type
- Search
- robots.txt token
DuckAssistBot- Follows robots.txt
- Yes, per DuckDuckGo
- IP ranges
- Published
- Blocked by name
- 5.3% of top sites
What is DuckAssistBot?
DuckAssistBot is DuckDuckGo's search crawler: it indexes pages for search results. In DuckDuckGo's words:
“DuckAssistBot is a web crawler for DuckDuckGo Search that crawls pages in real-time for our AI-assisted answers, which prominently cite their sources. This data is not used in any way to train AI models.”
DuckAssistBot user agent string
DuckDuckGo documents this user agent string for DuckAssistBot:
DuckAssistBot/1.2; (+http://duckduckgo.com/duckassistbot.html)
In robots.txt, use the token DuckAssistBot, not the full string. Crawlers match on the token, and version numbers in the full string can change.
How many websites block DuckAssistBot?
In our Oct 8, 2026 check of 817 of the most-visited websites, 5.3% block DuckAssistBot by name for their whole site (43 sites).
| robots.txt rule for DuckAssistBot | Sites | Share |
|---|---|---|
| Blocks the whole site by name | 43 | 5.3% |
| Blocks part of the site by name | 14 | 1.7% |
| Names it but doesn't block it | 1 | 0.1% |
| Blocked only by a catch-all (*) rule | 29 | 3.5% |
For comparison, 0.1% of the same sites block Googlebot by name. The sites are the top 1,000 origins in the Chrome UX Report for August 2026; see how we measured.
How to block DuckAssistBot in robots.txt
Add this group to the robots.txt file at the root of your domain to block DuckAssistBot from your whole site:
User-agent: DuckAssistBot Disallow: /
To block only part of your site, list those paths instead:
User-agent: DuckAssistBot Disallow: /private/
A group that names DuckAssistBot replaces your User-agent: * rules for it entirely (RFC 9309). If your catch-all group blocks paths that DuckAssistBot should also stay out of, repeat them in its group. To let DuckAssistBot in while a catch-all rule blocks others:
User-agent: * Disallow: / User-agent: DuckAssistBot Allow: /
“Once you’ve updated the file to disallow the DuckAssistBot user agent, the change will take effect after 72 hours and DuckAssistBot will stop crawling your site.”
What happens if you block DuckAssistBot?
“Opting out of DuckAssistBot does not impact organic search rankings and will not affect whether or not websites appear in our search results.”
How to verify requests from DuckAssistBot
DuckDuckGo publishes the IP addresses DuckAssistBot uses. Check a request's IP address against that list before trusting its user agent, which any client can fake.
See every AI crawler and how often top sites block it
Sources
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