This question already has an answer here:
-
Detecting the system DPI/PPI from JS/CSS?
12 answers
I have a container with every measurement defined in 'mm' for printing purposes. However, I want to show its preview inside a 600px wide block with perfect fit. What would be the best way to scale it down?
The millimiter to pixels and vice-versa formula takes the DPI of the screen into consideration.
DPI meaning dots-per-inch.
There's no truth in mm to pixels unless you have a stable DPI value you can use.
Anyway, this is the formula:
mm = (pixels * 25.4) / dpi
The most-usual seen DPI values seen are 72 and 96 if I'm not mistaken, but since this is for print it will most likely depend on the printer settings
I found this website that converts pixels to mm or vice versa: http://www.unitconversion.org/typography/millimeters-to-pixels-y-conversion.html
According to it, 600px is approximately 159mm.
However there is a problem. Pixel size depends on the resolution of the screen so I'm not really sure how that website came up with its conversion.
1 millimeter = 3.779527559055 pixel
therefore: 600px/3.7xxxx = 158.75