What is A3 size in inches?

To know exactly an A3 size in inches, you can apply the following formula: 1 millimetre is 0.0393701 inch. A3 size in millimetres is 297 millimetres x 420 millimetres. To answer the question “What is A3 size in inches?”, we need to multiply the number of millimetres by 0.0393701 inches. The result of this calculation is the following:

Millimetres to inches

297 mm x 0.0393701 inch = 11.6929 inch

420 mm x 0.0393701 inch = 16.535 inch

An A3 size in inches is 11.6929 x 16.535 inches.

Rounded to 2 decimals this is 11.69 x 16.54 inches.

Inches to millimetres

11.6929 inch / 0.0393701 inch = 297 mm

16.535 inch / 0.0393701 inch = 420 mm

An A3 size in millimeters is 297 x 420 mm.

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Table with A3 size in inches

Size Inches
4A0 66.220 x 93.622
2A0 46.811 x 66.220
A0 33.110 x 46.811
A1 23.386 x 33.110
A2 16.535 x 23.386
A3 11.693 x 16.535
A4 8.268 x 11.693
A5 5.827 x 8.268
A6 4.134 x 5.827
A7 2.913 x 4.134
A8 2.047 x 2.913
A9 1.457 x 2.047
A10 1.024 x 1.457

American paper sizes

American paper sizes are based on inches. Elsewhere around the world, the ISO 216 standard is often used. The American paper sizes Letter, Legal and Ledger, are indicated in inches.

An inch is a measure of length used in English-speaking countries. The unit symbol of inch is in or ″. An inch is by definition exactly equal to 24.4 mm. The length of an inch is approximately equal to the width of the upper phalanx of the finger of an adult male.

Other units

To display the A3 size in millimetres and centimetres, please refer to the pages: A3 size in mm and A3 size in cm.