A4 Paper Size in mm and Inches
A4 = 210 x 297 mm (8.27 x 11.69 in), the ISO 216 worldwide standard document size. It is exactly half of A3 and double A5.
Open the interactive Standards & Sizes tool →Key facts
| Millimeters | 210 x 297 mm |
|---|---|
| Inches | 8.27 x 11.69 in |
| Standard | ISO 216, A-series |
| Aspect ratio | 1:√2 (1:1.414) |
| Typical use | Business documents, reports |
Frequently asked questions
What size is A4 in cm?
A4 is 21.0 x 29.7 cm (210 x 297 mm), equal to 8.27 x 11.69 inches.
Is A4 bigger than US Letter?
A4 (210 x 297 mm) is narrower but taller than US Letter (215.9 x 279.4 mm / 8.5 x 11 in).
How many A4 fit in A3?
Two. A3 (297 x 420 mm) is exactly twice the area of A4; folding A3 in half gives A4.
Related pages
A4 Paper Size is part of Standards & Sizes on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
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