Updating the smartphone user-agent of Googlebot

Tuesday, March 15, 2016

As technology on the web changes, we periodically update the user agents we use for Googlebot. Next month, we will be updating the smartphone user-agent of Googlebot:

Googlebot smartphone user-agent starting from April 18, 2016:

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; +https://www.google.com/bot.html)

Today, we use the following smartphone user-agent for Googlebot:

Mozilla/5.0 (iPhone; CPU iPhone OS 8_3 like Mac OS X)
AppleWebKit/600.1.4 (KHTML, like Gecko) Version/8.0 Mobile/12F70 Safari/600.1.4
(compatible; Googlebot/2.1; +https://www.google.com/bot.html)

We're updating the user-agent string so that our renderer can better understand pages that use newer web technologies. Our renderer evolves over time and the user-agent string indicates that it is becoming more similar to Chrome than Safari. To make sure your site can be viewed properly by a wide range of users and browsers, we recommend using feature detection and progressive enhancement.

Our evaluation suggests that this user-agent change should have no effect on 99% of sites. The most common reason a site might be affected is if it specifically looks for a particular Googlebot user-agent string. User agent sniffing for Googlebot is not recommended and is considered to be a form of cloaking. Googlebot should be treated like any other browser.

If you believe your site may be affected by this update, we recommend checking your site with the Fetch and Render Tool in Search Console (which has been updated with the new user-agent string) or by changing the user-agent string in Developer Tools in your browser (for example, via Chrome Device Mode). If you have any questions, we're always happy to answer them in our Webmaster help forums.