01 · Operator
Who operates Quantcastbot
- Company
- Quantcast
- Type
- Other bot
- Official docs
- quantcast.com
02 · Behavior
What Quantcastbot does
Quantcastbot visits the landing pages of advertisements for quality checks. It also crawls millions of sites daily for interest-based audience targeting. For that it extracts the title, description, headers and paragraph text.
03 · Impact
Why Quantcastbot matters for your site
If you allow it
- Ad quality checks can keep your ads running
- Content classification can matter if you sell ads through Quantcast
If you block it
- No search visibility benefit
- Content is used for ad targeting
04 · Allow
How to allow Quantcastbot
robots.txt
User-agent: Quantcastbot
Allow: /Cloudflare
# Security › WAF › Custom rules › Create rule
Expression: (http.user_agent contains "Quantcastbot")
Action: Skip › All Super Bot Fight Mode rules
# Also check Security › Bots: "Block AI bots" can block it regardless of robots.txt.WordPress
# WordPress serves a virtual robots.txt. Edit it with your SEO plugin:
# Yoast: SEO › Tools › File editor · Rank Math: General Settings › Edit robots.txt
User-agent: Quantcastbot
Allow: /nginx
# nginx serves every user agent by default.
# Make sure no rule like this blocks it:
# if ($http_user_agent ~* "Quantcastbot") { return 403; }Apache
# Apache serves every user agent by default.
# Make sure .htaccess has no rule like this:
# RewriteCond %{HTTP_USER_AGENT} Quantcastbot [NC]
# RewriteRule .* - [F,L]05 · Block
How to block Quantcastbot
Quantcastbot does not always follow robots.txt. Add a server or CDN rule if you need a hard block.
robots.txt
User-agent: Quantcastbot
Disallow: /Cloudflare
# Security › WAF › Custom rules › Create rule
Expression: (http.user_agent contains "Quantcastbot")
Action: BlockWordPress
# WordPress serves a virtual robots.txt. Edit it with your SEO plugin:
# Yoast: SEO › Tools › File editor · Rank Math: General Settings › Edit robots.txt
User-agent: Quantcastbot
Disallow: /nginx
# In your server { } block:
if ($http_user_agent ~* "Quantcastbot") {
return 403;
}Apache
# .htaccess
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} Quantcastbot [NC]
RewriteRule .* - [F,L]
</IfModule>06 · User agents
User agents we see for Quantcastbot
The user agent published by the operator:
Quantcastbot/1.0 (+https://www.quantcast.com/bot)07 · Verification
Is it really Quantcastbot?
Quantcastbot’s operator publishes no IP ranges or hostnames, so requests cannot be verified. Treat the user agent as a claim, and watch your logs for unusual request rates.
FAQ
Questions about Quantcastbot
Does Quantcastbot obey robots.txt?
Partly. Quantcast says it honors disallows for audience crawling but ignores robots.txt when checking ad landing pages.
How do I verify Quantcastbot?
Compare the request IP with the short list of IP addresses that Quantcast publishes on its bot page.
Why does Quantcastbot visit my site?
It either checks a page used as an ad landing page or reads your content to classify it for audience targeting.
Last reviewed Oct 8, 2026