BingAds is a bot in the advertising and marketing bots category, operated by Microsoft.
AdIdxBot is the crawler used by Bing Ads. AdIdxBot crawls ads and follows the websites from those ads for quality control. Just like Bingbot, AdIdxBot has both “desktop” and “mobile” variants.
Advertising bots review landing pages, check ad placements and classify pages for brand safety and contextual targeting. Blocking ad verification bots can stop your ads or your inventory from serving, so allow the ones your ad partners use.
Sample user agent strings sent by BingAds:
Mozilla/5.0 (compatible; adidxbot/2.0; +http://www.bing.com/bingbot.htm)Mozilla/5.0 (iPhone; CPU iPhone OS 7_0 like Mac OS X) AppleWebKit/537.51.1 (KHTML, like Gecko) Version/7.0 Mobile/11A465 Safari/9537.53 (compatible; adidxbot/2.0; +http://www.bing.com/bingbot.htm)Anyone can copy a user agent string. Transfon Security also checks where each request comes from, so a request that claims to be a known crawler but comes from the wrong network is treated as a fake, not as the real crawler.
Share of BingAds requests to sites protected by Transfon Security in the 7 days to 27 October 2026.
| United States | 100% |
| Microsoft Corporation AS8075 | 100% |
Genuine BingAds IPs resolve to hostnames ending in msn.com. Run a reverse DNS lookup on the IP, then a forward lookup on the hostname, and check both match:
host 203.0.113.10 # the IP from your logs host crawl-name.msn.com # must return the same IP
We have not confirmed whether BingAds follows robots.txt. Add a rule, then check your logs to see that it stopped. robots.txt is a plain text file at the root of your domain, such as https://example.com/robots.txt.
User-agent: adidxbot Disallow: /
User-agent: adidxbot Disallow: /private/ Disallow: /search
User-agent: adidxbot Allow: /blog/ Disallow: /
User-agent: adidxbot Allow: / User-agent: * Disallow: /
User-agent: adidxbot group, BingAds ignores your User-agent: * rules, so repeat any that should still apply.adidxbot from BingAds's user agent; check Microsoft's own documentation if it publishes a different robots.txt name.Treat robots.txt as a statement of your policy, and enforce it where requests arrive.
Ad verification and contextual crawlers like BingAds can decide whether your pages get demand. Blocking the ones your partners use can lower fill rates.
Transfon Security for publishersBingAds checks pages for ad platforms. Its visits to landing pages are not users, so exclude them from conversion data.
Transfon Security for advertisersAd platforms send crawlers like BingAds to check product landing pages. Keep it allowed so ads are not disapproved, and out of analytics.
Transfon Security for e-commerceAllow BingAds on landing pages linked from your ads, and keep it off the app.
Transfon Security for SaaS and APIsrobots.txt is a request, not an enforcement. Transfon Security shows BingAds by name in the Top Bots report, so you can see how often it visits and which pages it reads. Block or allow it with a User Agent rule, or slow it down with a rate limit decision rule.
Transfon Security
BingAds is a bot in the advertising and marketing bots category, operated by Microsoft. AdIdxBot is the crawler used by Bing Ads. AdIdxBot crawls ads and follows the websites from those ads for quality control. Just like Bingbot, AdIdxBot has both “desktop” and “mobile” variants.
We have not confirmed whether BingAds follows robots.txt. Add a robots.txt rule, then check your logs to see that it stopped, and block it by user agent if it did not.
Add "User-agent: adidxbot" followed by "Disallow: /" to the robots.txt file at the root of your site. To enforce it, block requests whose user agent contains "adidxbot" at your WAF. In Transfon Security that is one User Agent block rule.
No. robots.txt is voluntary, so BingAds may not follow it, and anyone can send BingAds's user agent, so a fake BingAds ignores your rule. Enforce the rule where requests arrive, at your WAF, and check the source network.
Run a reverse DNS lookup on the IP. Genuine BingAds IPs resolve to a hostname ending in msn.com, and a forward lookup of that hostname returns the same IP. Anything else using its user agent is an impersonator.
Advertising bots review landing pages, check ad placements and classify pages for brand safety and contextual targeting. Blocking ad verification bots can stop your ads or your inventory from serving, so allow the ones your ad partners use.
Transfon Security identifies every bot in this directory in your traffic reports, flags fake search crawlers, and lets you allow, block or rate limit each bot.
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