# Areas Of A Series Paper Sizes

## A Paper Size Areas - Quick Lookup

Select the standard paper size from the 'Size' selector and the unit from the 'Unit' selector - the area will be shown in the area box.

 Size Unit Area 4A0   2A0   A0   A1   A2   A3   A4   A5   A6   A7   A8   A9   A10 in sq mm   sq cm   sq m   sq in   sq ft   sq yd is 0.06237

The area of each of the A paper sizes are set by the A paper size definitions (see below). A0 is defined as having an area of 1 square metre, however the A paper size standard also specifies that each size is rounded to the nearest millimetre. Thus A0 is 841mm x 1189mm giving an area of 0.999949 square metres.

Theoretically the area of a sheet of paper of size An can be calculated as 1/22 m2.

The following table gives theoretical areas compared with actual areas for each of the A paper sizes from 4A0 to A10

## Table of Theoretical and Actual Areas of A Paper Sizes

SizeTheoretical Area (sq m)Actual Area (sq m)Difference (sq m)Difference (%)
4A043.9997960.0002040.0051%
2A021.9998980.0001020.0051%
A010.9999490.0000510.0051%
A10.50.4995540.0004460.0892%
A20.250.249480.000520.208%
A30.1250.124740.000260.208%
A40.06250.062370.000130.208%
A50.031250.031080.000170.544%
A60.0156250.015540.0000850.544%
A70.00781250.007770.00004250.544%
A80.003906250.0038480.000058251.4912%
A90.0019531250.0019240.0000291251.4912%
A100.00097656250.0009620.00001456251.4912%

At the smaller sizes (A8, A9 & A10) the discrepancy between the theretical area of the sheet and the actual area is about 1.5%. Larger sizes have significantly lower differences between the theoretical area and the actual area.

## A Series Paper Sizes Defined

The A series paper sizes are defined in ISO 216 by the following requirements:

• The length divided by the width is 1.4142
• The A0 size has an area of 1 square metre.
• Each subsequent size A(n) is defined as A(n-1) cut in half parallel to its shorter sides.
• The standard length and width of each size is rounded to the nearest millimetre.

Note: For reference the last item is there because the root 2 aspect ratio doesn't always give a whole number.