Google To Rename GoogleBot With Dynamic User Agent

Google announced it is changing the user agent name of the current GoogleBot in December. We knew this was coming when Google launched the new Evergreen GoogleBot.

Google didn't change the user agent from Chrome 41 to what it was really running to not cause issues for some who hard coded scripts for user agent detection. The only way to see which version of Chrome GoogleBot was running was to see what features that GoogleBot can render.

Starting in December, GoogleBot's user agent will communicate that information.

Googlebot user agents today

Desktop: Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)

OR

Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Safari/537.36

In December, the new evergreen GoogleBot user agent

In December Google will start updating the above user agent strings to reflect the version of Chrome used in Googlebot. In the following user agent strings, "W.X.Y.Z" will be substituted with the Chrome version Google is using. For example, instead of W.X.Y.Z you'll see something similar to "76.0.3809.100". This version number will update on a regular basis.

Mobile: Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/W.X.Y.Z Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)

Desktop: Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)

OR

Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +http://www.google.com/bot.html) Chrome/W.X.Y.Z Safari/537.36

You can prepare for this by using the Chrome dev tools to change your user agent to one of these new GoogleBots and see what GoogleBot can see.

Outside of that, most sites really shouldn't have an issue with this. Those doing user agent sniffing and then special things based on that for GoogleBot will have to update their code.

Martin Splitt from Google said do not assume it would always have Chrome in it as well:

I wouldn't make that assumption (:

— Martin Splitt @ 🇨🇭🏡 (@g33konaut) October 2, 2019

Here are some more tweets from Googlers on this:

Time to double-check *if* and *how* you do UA sniffing to detect Googlebot 😎 https://t.co/E95oow0Kpm

— Martin Splitt @ 🇨🇭🏡 (@g33konaut) October 2, 2019

On today's news: is your ad-blocker detection script removing your site from search engines? The answer might shock you! pic.twitter.com/jBbn8030J3

— Gary "鯨理" Illyes (@methode) October 2, 2019

Here is from Bing:

When I was working on the crawler, anytime we considered a UA change, we quickly gave up out of fear that too many things would break with sites that do hardcoded UA detection. But sometimes updating the UA *is* the right thing to do.

— Frédéric Dubut (@CoperniX) October 2, 2019

You have until December to prepare for this.

Forum discussion at Twitter.