A3 paper size in cm, mm, inches and pixels
A3 is 29.7 × 42 cm (297 × 420 mm, or 11.69 × 16.54 inches).
A3 dimensions in every unit
| Unit | Width | Height |
|---|---|---|
| Millimetres | 297 mm | 420 mm |
| Centimetres | 29.7 cm | 42 cm |
| Inches | 11.69 in | 16.54 in |
| Points (1/72 in) | 842 pt | 1191 pt |
A3 in pixels at common resolutions
| Resolution | Width | Height | Typical use |
|---|---|---|---|
| 72 dpi | 842 px | 1191 px | PDF and design software default |
| 96 dpi | 1123 px | 1587 px | Browser and screen CSS |
| 150 dpi | 1754 px | 2480 px | Draft and large-format print |
| 300 dpi | 3508 px | 4961 px | Standard print quality |
Pixels are the size in inches multiplied by the resolution: 11.693 in × 300 = 3508 px.
About A3 paper
A3 is two A4 sheets side by side, and folded in half it becomes A4. It is a common size for posters, charts, drawings, artwork and presentation boards, and many print shops and some office printers handle it.
Most home printers stop at A4. To print an A3 file at home you can scale it to 71% to fit A4, or print it in tiles across two A4 sheets. An A3 sheet laid flat fits a C3 envelope (324 × 458 mm).
For screen or web graphics at A3, 150 dpi gives 1754 × 2480 pixels, which is enough for a poster viewed at arm’s length. 300 dpi is the usual target for close-up detail.
A3 compared with the other A sizes
Each A size is half the area of the one before, and every sheet has the same 1 : 1.414 shape. This table shows how many A3 sheets fill each size:
| Size | Dimensions | A3 sheets per sheet |
|---|---|---|
| A0 | 841 × 1189 mm | 8 |
| A1 | 594 × 841 mm | 4 |
| A2 | 420 × 594 mm | 2 |
| A3 | 297 × 420 mm | 1 |
| A4 | 210 × 297 mm | 1/2 |
| A5 | 148 × 210 mm | 1/4 |
| A6 | 105 × 148 mm | 1/8 |
| A7 | 74 × 105 mm | 1/16 |
| A8 | 52 × 74 mm | 1/32 |
The full table of sizes, including B series, US sizes and envelopes, is on the paper sizes page.
Frequently asked questions
What size is A3 in cm?
A3 is 29.7 x 42 cm (297 x 420 mm).
What size is A3 in inches?
A3 is 11.69 x 16.54 inches.
What size is A3 in pixels?
At 300 dpi A3 is 3508 x 4961 pixels, at 150 dpi it is 1754 x 2480 pixels, and at 72 dpi it is 842 x 1191 pixels.
How many A4 sheets make A3?
Two A4 sheets make one A3.
How many A3 sheets make A2?
Two A3 sheets make one A2.
What is the area of A3?
A3 is 0.1247 square metres (297 x 420 mm). A0 is defined as one square metre and every step down halves the area.