This page is using system (UI default) font

Physical and Device Independent Pixels (1/96th of inch)
100px
100dip size
100dip size and borders
Note 1: on 125% screen scale factor these rectangles will have different sizes. Last rectangle will have wider borders. Note 2: lengths are rounded to nearest pixel

font-size:16px

font-size:16dip

Current window resolution is pixels per inch, pixels per dip.