Units of paper quantity Units of paper quantity Various measures of paper quantity have been and are in use. Although there are no S.I. units such as quires and bales, there are ISO and DIN standards for the ream. Expressions used here include U.S. Customary units. A quire of paper is a measure of paper quantity. The usual meaning is 25 sheets of the same size and quality: of a ream of 500 sheets. Quires of 25 sheets are often used for machine-made paper, while quires of 24 sheets are often used for handmade or specialised paper of 480-sheet reams. (As an old UK
Paper size the sheet of paper is folded in half widthwise, let "c" be the length of the new short side: "c" = . If we take the ratio of the newly folded paper we have: formula_3 Therefore, the aspect ratio is preserved for the new dimensions of the folded paper. Weights are easy to calculate as well: a standard A4 sheet made from 80 g/m paper weighs 5 g (as it is of an A0 page, measuring 1 m), allowing one to easily compute the weight—and associated postage rate—by counting the number of sheets used. The advantages of basing a paper