A4 paper size in centimetres (cm).
A piece of A4 paper measures 21 x 29.7 cm or 210 x 297 mm. Like the other types of paper in the A series, the size of a sheet of A4 is defined by the international standard ISO 216 and is used in most countries. It was the German scientist Lichtenberg who, in 1786, described the proportions between the width and length of the A series. Then, in 1922, Portsmann and the German Institute for Standardisation outlined the format DIN 476, which would go on to become the current standard known as ISO 216.
A4 paper size in inches.
‘A’ series formats aren’t very common in the United States and Canada. However, for other countries that still use the imperial British way of measurement, dimensions are often expressed in inches. The measurements of A4 paper are 8.27 x 11.67 inches and they conserve the ratio between width and length of √2.
A4 paper size in pixels.
It’s just as important to know the pixel values of A4 if you wish to print images in this format. This depends on the resolution of the image, which is expressed in dpi (dots per inch). For example, the A4 format of an image with a resolution of 300 dpi can be obtained with 2480 x 3508 pixels.