ABCDEFG
1
2
Tell me the dimensions ofAspect ratio1.414213562
3
A4Area of A0 (mm2) 1,000,000
4
Conversion constant 2
5
mmcmReference
6
Long side29729.7Sizes
7
Short side21021.0
8
9
1/2 long side14914.9
10
1/3 long side999.9
11
2/3 long side19819.8
12
13
This calculator uses the proportionality of A-series paper to calculate a sheet's dimensions. A-series paper has two constants: the aspect ratio (the square root of 2) and the area of a sheet of A0 paper (1 metre squared).

As the number of the size increases by 1, the area of the sheet is halved, so the formula divides the area of an A0 sheet by 2 to the power of the number of the size.

So we can calculate the dimensions of any numbered size of A-series paper purely using a formula to perform the calculation, without storing any values except those shown. Just click on a cell to see the formula for that dimension.
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100