User agent is a string used by web servers to identify a web browser they are connected to. Web servers need to identify every web browser they are connected to to be able to know how they should serve the associated browser. For instance, if a web server identifies a browser as Firefox running on Android, it will serve web pages specialized for mobile device instead of desktop. User agent itself is one of the elements on HTTP header.
Every web browser has a different user agent. And since it is only used as an identifier for the web server side, most web browsers don’t provide a way for users to view their user agent. But, in case you are curious about the user agent of the web browser you are using, there are several resources you can take advantage of. One of which is the tool provided by WhoIsHostingThis.com. Simply visit this page to view the user agent of your web browser.
Following is the example of the user agent of Google Chrome version 69 running on Windows 10.
You might be wondering, why is the user agent of Google Chrome on Windows 10 so complicated?
It is because Google Chrome is a web browser that came later. At the beginning of the modern web browser development, web servers only recognized Mozilla as a modern web server that supported frames. Even after Internet Explorer emerged later. It forced other web browsers that came later to add the words like “Mozilla” and “Gecko” in order to make web servers serve framed web pages like they did to Mozilla.
User agent itself is editable. For instance, if you are using Google Chrome running on Windows 10, you can change the user agent to Firefox on iPhone so the web servers will serve the web pages specialized for mobile device, iPhone in this case.
In addition to the tool provided by WhoIsHostingThis, another tool you can use to view the user agent of the web browser you are using is the one provided by WhatIsMyBrowser.com.