A photo can look crisp on a small screen and still contain too few pixels for a large print. Start with the image's actual width and height in pixels, then choose a physical size. The file size in megabytes is not a reliable substitute: compression, image content and file format all change it.
The calculation you need
For an uncropped image, divide pixel width by print width in inches. Do the same for height. A 3,000 × 2,400 pixel image printed at 10 × 8 inches gives 300 pixels per inch on both axes. Printing the same file at 15 × 12 inches gives 200 PPI. The image has not gained or lost pixels; they are spread over a different area.
Pick a target for the job
Use your print provider's requirement when one is available. Our checker starts at 300 PPI as a useful planning target for close-viewed photographs, but this is not a promise of quality. Viewing distance, focus, compression, paper and the printer all affect the result. An image that passes the pixel calculation may still look soft because the original is out of focus.
| Print size | Pixels at 300 PPI | Pixels at 200 PPI |
|---|---|---|
| 6 × 4 in | 1,800 × 1,200 | 1,200 × 800 |
| 10 × 8 in | 3,000 × 2,400 | 2,000 × 1,600 |
| 12 × 8 in | 3,600 × 2,400 | 2,400 × 1,600 |
Allow for the crop
A 3,000 × 2,000 image has a 3:2 shape. An 10 × 8 inch print has a 5:4 shape. To fill the print without stretching, you retain a 2,500 × 2,000 region: 250 PPI, rather than 300. In our checker, choose Crop to fill to include this loss. Choose Fit whole image to keep every pixel and accept blank space around the picture.
Before ordering
- Use the original image, rather than a screenshot or a messaging-app copy.
- Check the final crop, especially faces, text and edges.
- Inspect a small section at full pixel size for blur and compression.
- For a large or important order, print a small proof first.
Changing only a file's resolution tag does not restore missing detail. Adobe explains the distinction between pixel count and print density in its printed image resolution guide.