Robot Web Crawlers

Robot Function Device Percentage User Agent
Googlebot Search Engine Mobile 8.5% Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.96 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
AdsBot Google Advertising Bot Mobile 5.8% Mozilla/5.0 (iPhone; CPU iPhone OS 9_1 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13B143 Safari/601.1 (compatible; AdsBot-Google-Mobile; +http://www.google.com/mobile/adsbot.html)
Googlebot Search Engine Mobile 5.3% Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Safari/537.36
Googlebot Search Engine Desktop 4.3% Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Googlebot Images N/A 2.3% Googlebot-Image/1.0
Googlebot Media Partner N/A 0.8% Mediapartners-Google
BingBot Search Engine Desktop 8.4% Mozilla/5.0 (compatible; bingbot/2.0; +http://www.bing.com/bingbot.htm)
BingPreview Search Engine Mobile 7.9% Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534+ (KHTML, like Gecko) BingPreview/1.0b
BingBot Search Engine Mobile 5.8% 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; bingbot/2.0; +http://www.bing.com/bingbot.htm)
Facebook Social Media Agent Desktop 2.6% facebookexternalhit/1.1 (+http://www.facebook.com/externalhit_uatext.php)
Facebook Social Media Agent Desktop 0.3% facebookexternalhit/1.1
Yahoo! Slurp Search Engine Desktop 0.13% Mozilla/5.0 (compatible; Yahoo! Slurp; http://help.yahoo.com/help/us/ysearch/slurp)
Sogou Spider Search Engine Desktop 4% Sogou web spider/4.0(+http://www.sogou.com/docs/help/webmasters.htm#07)
Proximic Search Engine Desktop 1.7% Mozilla/5.0 (compatible; proximic; +https://www.comscore.com/Web-Crawler)
Baidu Spider Search Engine Desktop 1.1% Mozilla/5.0 (compatible; Baiduspider/2.0; +http://www.baidu.com/search/spider.html)

Source: Device Atlas