ISO A-Series Sizes
| Size | Millimetres | Approx. inches |
|---|
| A0 | 841 × 1189 | 33.1 × 46.8 |
| A1 | 594 × 841 | 23.4 × 33.1 |
| A2 | 420 × 594 | 16.5 × 23.4 |
| A3 | 297 × 420 | 11.7 × 16.5 |
| A4 | 210 × 297 | 8.27 × 11.69 |
| A5 | 148 × 210 | 5.83 × 8.27 |
| A6 | 105 × 148 | 4.13 × 5.83 |
| A7 | 74 × 105 | 2.91 × 4.13 |
| A8 | 52 × 74 | 2.05 × 2.91 |
| A9 | 37 × 52 | 1.46 × 2.05 |
| A10 | 26 × 37 | 1.02 × 1.46 |
How A-Series Sizes Relate
Each smaller A-series size is formed by halving the preceding sheet parallel to its shorter side. The series maintains approximately the same 1:√2 aspect ratio.
Common Uses
| Size | Typical examples |
|---|
| A3 | Larger diagrams, posters, folded A4 spreads |
| A4 | Common office documents and letters |
| A5 | Small booklets, notepads |
| A6 | Postcard-sized material |