[darkerside]

Aren't screen sizes typically based on that diagonal size (i.e. a 15" screen is a diagonal 15")? If so, doesn't that make parent's link more accurate?

[kbutler]

Screen sizes are reported on the diagonal, but the makers are not constrained to maintain the same diagonal size with different apsect ratios. For instance, the pixel Chromebooks have 12.82" and 12.3" diagonal screens. I've never seen a 16:9 laptop with those sizes.

And specifically for an xps 13 device, where they trim excess bezels, etc., the keyboard width becomes the limiting factor.