Choose the size for the job
If a 4 × 6 crop already has the composition you want, the crop geometry can be reused. Export from the original source, however, instead of enlarging a small downloaded version. The larger physical print spreads every retained pixel over more space.
| Measurement | Value |
|---|---|
| Inches | 20 × 30 |
| Centimetres | 50.8 × 76.2 |
| Millimetres | 508 × 762 |
| Short-edge-to-long-edge ratio | 2:3 |
Pixel examples
These examples multiply each edge in inches by the stated PPI. They describe pixel counts for the chosen size, not a universal pass or fail rule for appearance. Use the retained pixels after cropping when checking an existing photo.
| Example PPI | Pixels |
|---|---|
| 150 | 3,000 × 4,500 |
| 240 | 4,800 × 7,200 |
| 300 | 6,000 × 9,000 |
A worked example
A 6000 × 4000 file placed at 30 × 20 inches gives 200 PPI. At 20 × 13⅓ inches the same file gives 300 PPI. Neither calculation changes the image. They describe two possible physical sizes for the existing data and make the tradeoff visible.
Before you print
On A1 paper, a centred portrait 20 × 30 rectangle leaves 43 mm at the sides and 39.5 mm at the top and bottom. Before exporting, confirm both the supported media size and the printable margins. The screen preview does not simulate paper texture, printer sharpening, or the final colour response.