Megapixels needed for print sizes
A 4x6 needs 2.2 megapixels at 300 dpi; an 8x10 needs 7.2; a 16x20 needs 28.8.
Megapixels needed for each print size
Megapixels = (width in inches × dpi) × (height in inches × dpi) ÷ 1,000,000. These are the pixels in the print itself; a camera image of a different shape needs more, as the crop tables on each size page show.
The biggest print each camera can make without upscaling
| Camera | At 300 dpi | At 200 dpi | At 150 dpi |
|---|---|---|---|
| 12 MP phone (4032 × 3024) | 10.1 × 13.4 in | 15.1 × 20.2 in | 20.2 × 26.9 in |
| 24 MP camera (6000 × 4000) | 13.3 × 20 in | 20 × 30 in | 26.7 × 40 in |
| 48 MP phone (8064 × 6048) | 20.2 × 26.9 in | 30.2 × 40.3 in | 40.3 × 53.8 in |
These sizes are the full image, before any crop to a print shape. For a 12-megapixel phone, 300 dpi gives about 10 × 13.4 inches, so a 8x10 or 8x12 print is comfortably sharp, while a 16x20 is about 190 dpi after cropping.
Is more megapixels always better?
For prints, only up to the point where the pixels in the file match the print at your chosen dpi. Beyond that, extra pixels do not show. A 24-megapixel file (6000 × 4000) printed at 4x6 inches is 1,000 dpi, far more than a print can show; the same file at 24x36 inches is 167 dpi. Match the file to the print and the viewing distance, not to the camera spec. See paper size in pixels for A4 and Letter.
Frequently asked questions
How many megapixels for an 8x10 print?
7.2 megapixels for 300 dpi, 3.2 for 200 dpi.
How many megapixels for a 4x6 print?
2.2 megapixels at 300 dpi.
How many megapixels for a 16x20 print?
28.8 megapixels at 300 dpi, 12.8 at 200 dpi, 7.2 at 150 dpi.
Is 12 megapixels enough for a poster?
For 18x24 inches at 150 dpi (2700 x 3600) yes; for 24x36 at 150 dpi (19.4 MP) it is not quite.
How many pixels is 300 dpi?
Multiply the print size in inches by 300 on each side.