New: See someone else's User Agent!

What is a "User Agent" anyways?

A User Agent is a short string that web browsers and other applications send to identify themselves to web servers. The format is defined in RFC 7231.

Unfortunately, most browsers falsify part of their User-Agent header in an attempt to be compatible with more web servers. Here is a rather humorous history of how it all started.


  • Click on your user-agent string (at the top) to get a link that you can share with other people.
  • Visit[any-user-agent-string], the site will give you a breakdown for that string.
  • If something is missing or wrong, or you have any other ideas for improving the site, please send an issue or pull request on Github.