# A4 size in centimetres

The A4 paper size in cm is 21 x 29.7 cm. The A series starts with A0. An A0 is one square meter. An A1 is half of an A0. The area of an A1 is, therefore, half a square meter. The length to width ratio of an A0 and all sizes in the A series are √2:1. The area of an A4 is ½ × ½ × ½ = 1/16 m². The ratio between the long side and short side of a size from the A series is the width (B) = length (L)/2. For more information see also What is A4 size in cm?

Using the calculator below you can calculate the A4 size in centimetres. Besides calculating A4 sizes in centimetres, you can also calculate the other A sizes with this calculator, in various units. Select the A size and then choose the desired unit. The result will be shown undersize.

### Overview A-size in centimetres

Overview of A4 size in centimetres (cm).

Size Centimeter
4A0 168.2 x 237.8
2A0 118.9 x 168.2
A0 84.1 x 118.9
A1 59.4 x 84.1
A2 42.0 x 59.4
A3 29.7 x 42.0
A4 21.0 x 29.7
A5 14.8 x 21.0
A6 10.5 x 14.8
A7 7.4 x 10.5
A8 5.2 x 7.4
A9 3.7 x 5.2
A10 2.6 x 3.7

### Other units such as millimetres, pixels and metres.

Choose from the units below for the A4 size in Micrometres (μm), Millimetres (mm), Meters (m), Thou (th), Inches (in), Feet (ft), Yards (yd), Pixels, Pica, Point and HPGL.