Jquery $(window).width more than expected

In JavaScript, using the following code on a Samsung S5:

alert( $( window ).width() );

I get a value of 980.

When I go to the site:

I get a value for "px dimensions width" of 360px.

1) Why the difference ?

2) How do I then go about detecting the real 360px width using jquery?

Thanks,

David

Solution

There is a difference between Real Resolution and CSS Resolution. It depends from pixel ratio. in S5 it is 3/1

For instance:

Samsung Galaxy S5 resolution:

Real resolution: 1080X1920

CSS resolution: 360X640