AdIdxBot: user agent, IP verification and robots.txt
AdIdxBot is operated by Microsoft. It is classified here as Retrieval (Bing Ads quality control). Verification method: None available.
Exact user-agent string
Mozilla/5.0 (compatible; adidxbot/2.0; +http://www.bing.com/bingbot.htm)
robots.txt token: adidxbot. The user-agent string is self-asserted and can be
forged by anyone. It is a claim, not proof.
How to verify AdIdxBot is genuine
Microsoft publishes no IP range file and no reverse DNS method for AdIdxBot. There is no way for anyone, including us, to prove a request claiming this identity is genuine.
How to block or allow AdIdxBot
User-agent: adidxbot
Disallow: /Replace Disallow with Allow to permit it explicitly.
What blocking AdIdxBot costs you
AdIdxBot crawls ads and follows the sites those ads point to, for quality control. If you advertise on Bing, blocking it interferes with the checks that keep your ads running. If you do not advertise, blocking it costs nothing.
What is specific to AdIdxBot
AdIdxBot is the reason loose log filters overcount Bing traffic. Its user-agent points at the same bingbot.htm URL as bingbot itself and differs only in the token, so a filter matching on the bot URL or on the word bing catches both and attributes ad crawling to search crawling. Microsoft documents desktop and mobile variants, mirroring bingbot's structure. Note also that Microsoft's published bingbot.json is presented as bingbot's range list and Microsoft does not state that it covers AdIdxBot, so an IP check against that file is not a documented verification path for this token.
Verify a request claiming to be AdIdxBot
Check a AdIdxBot request against Microsoft's published ranges
Source
Primary documentation: https://www.bing.com/webmasters/help/which-crawlers-does-bing-use-8c184ec0. Last verified 2026-08-02.
Other Microsoft crawlers
- Bingbot - Search index