YandexComBot
Yandex operates YandexComBot, a search engine crawler that indexes content for search in languages other than Russian. Its robots.txt token is YandexComBot; Yandex says it does not follow general robots.txt rules and needs an explicit robot-specific Disallow to be blocked. Verification is by reverse DNS to yandex.ru, yandex.net or yandex.com with forward confirmation; Yandex publishes no IP range list.
Mozilla/5.0 (compatible; YandexComBot/3.0; +http://ya.cc/bots)What YandexComBot does
The user-agent string is "Mozilla/5.0 (compatible; YandexComBot/3.0; +http://ya.cc/bots)". The link in the string, http://ya.cc/bots, redirects to Yandex's help page on checking Yandex robots. Yandex describes the crawler's job as indexing content for search in languages other than Russian, and says it can index content whenever there is no explicit robot-specific restriction. That wording means a page with no rule addressed to this bot is treated as open to it. Yandex does not document JavaScript execution.
Allowing YandexComBot keeps your pages eligible for Yandex search results in non-Russian languages. Blocking it removes them from that index, per the operator's description. A block has to name the bot. Yandex documents that this bot does not follow general robots.txt rules, so "User-agent: *" directives are ignored and it will index content unless a Disallow is placed under "User-agent: YandexComBot". This is why the registry records robots.txt support as partial.
Verification is by DNS. Reverse-resolve the requesting IP, confirm the hostname ends in yandex.ru, yandex.net or yandex.com, and then forward-resolve that hostname to check it maps back to the same IP. Yandex Webmaster also has an IP address check tool for the same purpose. Yandex publishes no IP range list for this crawler. A matching user-agent string on its own is not proof of origin, since the docs give DNS as the verification method.
Operator note. It does not take into account the general rules in robots.txt and needs an explicit robot-specific Disallow to be blocked. The UA links to http://ya.cc/bots, which redirects to Yandex's help page on checking Yandex robots.
Controlling YandexComBot with robots.txt
Use the token YandexComBot in robots.txt. Yandex documents limits on how this bot applies robots.txt; see the operator note.
User-agent: YandexComBot
Disallow: /User-agent: YandexComBot
Allow: /Verifying a request is really YandexComBot
Anyone can put YandexComBot in a User-Agent header. Reverse DNS lookup on the requesting IP must return a host ending in yandex.ru, yandex.net or yandex.com, and a forward DNS lookup of that host must return the same IP. Yandex Webmaster also provides an IP address check tool.
host <request-ip>
# expect a hostname ending in yandex.ru, yandex.net, yandex.com
host <that-hostname>
# expect it to resolve back to <request-ip>Common questions
Should I block YandexComBot?
Only if you do not want your pages indexed for Yandex search in non-Russian languages, which is the purpose Yandex documents. If you do block it, write the rule under "User-agent: YandexComBot", because Yandex says a general "User-agent: *" rule does not restrict this crawler.
Why does YandexComBot ignore my robots.txt?
Yandex documents that YandexComBot does not follow general robots.txt rules and can index content if there is no explicit robot-specific restriction. Directives under "User-agent: *" therefore have no effect. Add a section for "User-agent: YandexComBot" with the Disallow paths you want applied.
How do I verify YandexComBot?
Do a reverse DNS lookup on the source IP and check the hostname ends in yandex.ru, yandex.net or yandex.com. Then forward-resolve that hostname and confirm it returns the original IP. Yandex Webmaster also has an IP address check tool. Yandex does not publish an IP range list for this crawler.
Sources
Every fact on this page was checked against Yandex's own documentation, listed below, and re-checked by a second reviewer before publication. Reviewed September 2026.
Related crawlers
This registry documents how operators describe their own bots so site owners can identify and control them. It does not publish third-party IP lists or guess at undocumented behaviour. To see how your own site responds to automated visitors, the bot detection scanner reads a URL's live response and names the protection it finds.