A4 paper measures 210 × 297 millimeters, which is equivalent to 21 × 29.7 centimeters or approximately 8.3 × 11.7 inches
. It is part of the international ISO 216 A series paper sizes and is one- sixteenth the size of A0 paper, meaning it results from halving A0 paper four times
. This size is widely used globally for printing and stationery, except in some countries like the United States and Canada where different standards apply
