The size of A4 paper is 2 10 mm× 297 mm, and A3 paper is twice as long as A4 paper. The format specification of copy paper only adopts A series and B series. If A0 paper is divided into two halves along the length direction and A 1 paper is divided along the length direction, it becomes A2 specification.
According to the basic area of paper format, the format specifications are divided into A series, B series and C series. A0 has a folio size of 841mm×1189mm and a folio area of 1m2. B0 has a width of1000 mm×1414 mm, a width area of1.5m2, and c0 has a width of 9 17mm× 1279mm.