Pixel to MM equation?

Question

Is there a reliable equation to work out pixel size to MM? Or is that not possible cross device?

We are working with a bespoke system that delivers content to many

Answer 1

Late but may be useful. 1 px = 0.26458333333719 mm

Milli Meter Pixel 1 mm = 3.779527559 px

So if you have lets say 10px. It will be equal to 10 * 0.26458.. = 2.64mm ref : https://everythingfonts.com/font/tools/units/px-to-mm Enjoy :)