目前螢幕約為96DPI
1 Inch = 96 Pixels , 1 CM = 1/2.54 Inch = 96/2.54 Pixels = 37.7953 Pixels
列印網頁時瀏覽器會以螢幕的DPI為參考值(非印表機的DPI)

box1:38*38
box2:718*1043
box3:756*1081
A4:21*29.7cm(標準規格),實際約為21*29.6

FireFox+Kyocera FS-1040 GX
列印邊界都設為0
列印時仍有0.5cm的邊界
(21-0.5*2)*37.8=756
(29.6-0.5*2)*37.8=1081.08
box3