Here are some simple utility functions to convert the preprint unit pt
(defined as 1/72 inch) into inches
or mm
.
function convertPtToInch(pt) { return pt / 72; } function convertInchToMM(inch) { return inch * 25.4; } function convertPtToMM(pt) { return convertInchToMM(convertPtToInch(pt)); } // Example usage console.log(convertPtToMM(595)) // Prints 209.90277777777777
Note that while this conversion is exact, there is some tolerance required when comparing these units:
An ISO A4 paper is defined as 210x297 mm
– or 595x842 pt
.
However, converting 595×842 pt into mm results in 209.902777 mm
and 297.038888 mm
respectively. Watch out for those tolerances if you try to compare paper sizes. I recommend a tolerance of at least 0.25 mm
.