What is A4 size?

The A4 paper size is 210 mm by 297 mm. It’s the most commonly used paper size in Europe and Japan. The size is derived from an A0 sheet that has been halved four times. On this page, we answer the question: What is A4 size?

A0 relative to A4

An A0 sheet has a surface area of 1 m². The length-to-width ratio of an A0 sheet, and all sizes in the A-series, is √2:1. The area of an A4 sheet is 1/2 × 1/2 × 1/2 × 1/2 = 1/16 m².

A4 paper size international

A4 size is an international paper size originating from the DIN standard (DIN 476 from 1922). This standard has been updated to the ISO 216 standard. In some parts of Germany, people still refer to it as DIN A4. A4 is part of a series that includes A0, A1, A2, A3, A4, A5, A6, A7, and A8.

In North America and parts of Latin America, the ISO 216 standard isn’t used. Instead, the US Letter size of 8½ by 11 inches (215.9 mm by 279.4 mm) is used. It is approximately 6 mm wider and 18 mm shorter than A4. Most modern printers and copiers can accommodate both sizes.

Weight and mass

A commonly used weight for A4 paper is 80 gsm (grams per square meter). This ’80 gsm’ refers to the weight of an A0 sheet. An A0 sheet weighs 80 grams, and therefore an A4 sheet weighs 80 / 16 = 5 grams.

Different values

If you’re looking for the A4 paper size in different units, such as inches, centimeters, millimeters, and pixels, please explore the links below:

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