ISO A series
A3 paper size
A3 measures 297 x 420 mm (11.69 x 16.54 in). Drawings, diagrams, menus, small posters, spreadsheets.
297 x 420millimetres
11.69 x 16.54inches
3,508 x 4,961pixels @ 300 dpi
Dimensions in every unit
| Unit | Width x height |
|---|---|
| Millimetres | 297 x 420 mm |
| Centimetres | 29.7 x 42 cm |
| Inches (decimal) | 11.693 x 16.535 in |
| Inches (fraction) | 11 11/16 x 16 9/16 in |
| Points (1/72 in) | 841.9 x 1190.6 pt |
| Picas | 70.16 x 99.21 pc |
Pixel dimensions by resolution
| Resolution | Pixels | Megapixels |
|---|---|---|
| 72 dpi | 842 x 1,191 px | 1 MP |
| 96 dpi | 1,123 x 1,587 px | 1.8 MP |
| 150 dpi | 1,754 x 2,480 px | 4.4 MP |
| 200 dpi | 2,339 x 3,307 px | 7.7 MP |
| 300 dpi | 3,508 x 4,961 px | 17.4 MP |
| 600 dpi | 7,016 x 9,921 px | 69.6 MP |
300 dpi is the usual target for printed photos and artwork; 72–96 dpi is screen resolution.
Document size with bleed
| Bleed | Millimetres | Inches |
|---|---|---|
| 3 mm bleed (each side) | 303 x 426 mm | 11.929 x 16.772 in |
| 0.125 in bleed (each side) | 303.4 x 426.4 mm | 11.943 x 16.785 in |
How many A3 fit on a press sheet
| Sheet | Without bleed | With 3 mm bleed |
|---|---|---|
| A3 | 1-up | 0-up |
| SRA3 | 1-up | 1-up |
| 12 x 18 in | 1-up | 1-up |
| 13 x 19 in (Super B) | 1-up | 1-up |
| B2 (offset) | 2-up | 2-up |
| B1 (offset) | 4-up | 4-up |
Simple grid imposition with no gutters or gripper margin; real layouts may fit fewer.
Envelopes for A3
| Fold | Folded size | Envelopes that fit |
|---|---|---|
| Unfolded | 297 x 420 mm | C3 envelope |
| Folded in half | 210 x 297 mm | 9 x 12 catalog envelope, C4 envelope, 10 x 13 catalog envelope |
The √2 system
A3 has an aspect ratio of 1 : 1.4141 — close to √2 (1.4142). Folding or cutting it in half across the long side produces the next smaller size in the series with the same proportions, and two sheets side by side form the next larger size. This is why scaling between sizes in the series (for example on a photocopier) never crops or distorts the page.
Similar sizes
Frequently asked questions
What are the dimensions of A3?
A3 is 297 x 420 mm, which is 11.69 x 16.54 in (11 11/16 x 16 9/16 in).
How many pixels is A3 at 300 DPI?
3,508 x 4,961 pixels at 300 dpi, or 1,754 x 2,480 at 150 dpi.
Sources & data
- Dimensions per the relevant standard; see sources.