YandexDirectDyn user agent
Operated by Yandex
YandexDirectDyn is the Yandex robot that generates dynamic ad banners.
The YandexDirectDyn bot at a glance
- YandexDirectDyn is operated by Yandex and checks landing pages for an advertising platform.
- The robots.txt token for YandexDirectDyn is YandexDirectDyn.
- Blocking a platform fetcher has no effect on organic search rankings.
- YandexDirectDyn robots.txt support: Not for user-requested fetches.
- Recommendation for Generative Engine Optimization (GEO): Allow.
What is YandexDirectDyn?
Advertisers running dynamic Yandex ads should allow it.
Yandex lists this robot on its official page of Yandex robots.
Should you block YandexDirectDyn?
Allow YandexDirectDyn unless it causes a measurable load problem.
| Effect on search rankings | Blocking a platform fetcher has no effect on organic search rankings. |
|---|---|
| Effect on AI visibility | Blocking breaks the feature the fetcher serves, such as ad approval or feed updates. |
| Follows robots.txt | Not for user-requested fetches |
| Recommendation | Allow |
How to block or allow YandexDirectDyn
Put the robots.txt rule in the file at the root of every domain and subdomain, for example https://example.com/robots.txt. The token YandexDirectDyn is matched case-insensitively. robots.txt alone may not stop YandexDirectDyn, so add the Nginx, Apache or Cloudflare rule as well.
robots.txt: block
# Block YandexDirectDyn
User-agent: YandexDirectDyn
Disallow: /robots.txt: allow
# Allow YandexDirectDyn
User-agent: YandexDirectDyn
Allow: /robots.txt: partial
# Keep YandexDirectDyn out of private areas only
User-agent: YandexDirectDyn
Disallow: /wp-admin/
Disallow: /cart/
Disallow: /checkout/
Disallow: /my-account/
Allow: /Nginx
# Nginx: return 403 to YandexDirectDyn
if ($http_user_agent ~* "(YandexDirectDyn)") {
return 403;
}Apache
# Apache .htaccess: return 403 to YandexDirectDyn
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} (YandexDirectDyn) [NC]
RewriteRule .* - [F,L]Cloudflare WAF
# Cloudflare > Security > WAF > Custom rule, action: Block
(http.user_agent contains "YandexDirectDyn")How to verify real YandexDirectDyn traffic
Reverse DNS check: look up the request IP, confirm the hostname ends in yandex.ru, yandex.net, yandex.com, then look up that hostname and confirm it returns the same IP.
# 1. Reverse lookup: the hostname must end in yandex.ru, yandex.net, yandex.com
host REQUEST_IP
# 2. Forward lookup: must return the same REQUEST_IP
host HOSTNAME_FROM_STEP_1How to find YandexDirectDyn in your server logs
Search the web server access log for the token. The command below counts YandexDirectDyn requests per URL on Nginx or Apache.
grep -i "YandexDirectDyn" access.log | awk '{print $7}' | sort | uniq -c | sort -rn | head -20For a full report per AI bot, upload the log to the AI Log File Analyzer, a free tool by Justin Hà.
YandexDirectDyn user agent string
The full user agent Yandex publishes for YandexDirectDyn. Version numbers such as Chrome/W.X.Y.Z change over time, so match the token, not the whole string.
Mozilla/5.0 (compatible; YandexDirectDyn/1.0; +http://yandex.com/bots)YandexDirectDyn FAQ
YandexDirectDyn identifies itself with the robots.txt token "YandexDirectDyn". A typical request header reads: Mozilla/5.0 (compatible; YandexDirectDyn/1.0; +http://yandex.com/bots)
Partly. YandexDirectDyn fetches pages because a user asked for them, and Yandex says robots.txt rules may not apply to those user-requested fetches. Use a firewall rule if you must stop it.
Blocking a platform fetcher has no effect on organic search rankings. Blocking breaks the feature the fetcher serves, such as ad approval or feed updates.
Add two lines to the robots.txt file at the root of each domain and subdomain: "User-agent: YandexDirectDyn" followed by "Disallow: /". The token is case-insensitive. Changes can take up to 24 hours to be picked up.
Yes. Run a reverse DNS lookup on the request IP; a real YandexDirectDyn request resolves to yandex.ru, yandex.net, yandex.com, and a forward lookup of that hostname returns the same IP.
Search your server access log for "YandexDirectDyn", for example with: grep -i "YandexDirectDyn" access.log. The AI Log File Analyzer by Justin Hà counts visits per AI bot from an uploaded log file.
Sources: Yandex crawler documentation. Last reviewed by Justin Hà.
See which of these bots actually reach your website
The AI Log File Analyzer by Justin Hà counts visits from GPTBot, ClaudeBot, PerplexityBot and other AI crawlers in your server log, for free. The GEO Technical Package sets up robots.txt, llms.txt and crawler access for AI search.
