Sec-CH-UA-Mobile

Request headers

Says only whether the device is a phone; a single true or false flag.

On the wireSec-CH-UA-Mobile: …
CategoryRequest headers

Headers the browser attaches when it sends to the server.

How to read this

  • The first digit of a status code carries the meaning: 4 means the request, 5 means the server.
  • 404 means "not there"; 403 means "there, but not for you". Swapping them makes debugging slower.
  • Header names are case-insensitive — Content-Type and content-type are the same header.
  • Caching and CORS problems usually come down to one header line, visible in the browser’s network tab.

Frequently asked questions

Q. What does HTTP Sec-CH-UA-Mobile mean?

Says only whether the device is a phone; a single true or false flag.

Q. What does Sec-CH-UA-Mobile look like on the wire?

It travels as Sec-CH-UA-Mobile: …

Q. Where does Sec-CH-UA-Mobile appear?

In request headers.

Q. What group does Sec-CH-UA-Mobile belong to?

The request headers group; the rest of that group is listed further down.

Same group

Reference docs