what is a4 paper

A4 paper is a standard paper size used in many countries, including the UK and Europe. It measures 210 x 297 mm or 8.27 x 11.69 inches. A4 paper is part of the ISO 216 system, which has been internationally adopted and is printable in most common home and office printers. A4 is slightly larger than the close equivalent to US letter size, which measures 8.5 x 11 inches. A4 paper is commonly used for everyday printing and stationery. All subsequent A paper sizes are defined as half or double the size of the previous size, starting from A0.