What is a "User Agent"?

A User Agent is a short string that web browsers and other applications send to identify themselves to web servers.

Unfortunately, most browsers falsify part of their User-Agent header in an attempt to be compatible with more web servers.


  • Click on your user-agent string (at the top) to get a link that you can share with other people.
  • Visit whatsmyua.com/#[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 .

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