Print Size From Megapixels
Enter a camera's megapixel count and get the largest sharp print at 150, 300 and 600 DPI, with the viewing-distance rule that decides which one you need.
Enter megapixels and aspect ratio to see max print sizes at different quality levels.
This page starts from a megapixel count, which is what a camera spec sheet gives you. If you have the actual pixel dimensions of a file, the photo print size from pixel dimensions page takes those directly and does not have to assume an aspect ratio. Both divide pixels by DPI, so they agree whenever the shape matches.
Print size depends on your camera’s megapixels and the DPI (dots per inch).
The formula:
- Total pixels = Megapixels × 1,000,000
- Width (pixels) = sqrt(Total pixels × Aspect ratio)
- Print width (inches) = Width pixels / DPI
- Print width (cm) = Print width (inches) × 2.54
Standard camera aspect ratios:
- 3:2, most DSLRs and mirrorless cameras
- 4:3, most smartphones and compact cameras
- 16:9, video mode
- 1:1, square format
Print quality guidelines:
| DPI | Quality | Best for |
|---|---|---|
| 150 | Acceptable | Large posters viewed far away |
| 300 | High quality | Photos, magazines, brochures |
| 600 | Professional | Fine art, close inspection |
Common camera resolutions, all at 3:2 and stated width × height, the way the calculator reports them:
| Megapixels | Pixel dimensions | Max print at 300 DPI |
|---|---|---|
| 8 MP | 3464 × 2309 | 11.5 × 7.7 in (29.3 × 19.5 cm) |
| 12 MP | 4243 × 2829 | 14.1 × 9.4 in (35.9 × 23.9 cm) |
| 24 MP | 6000 × 4000 | 20.0 × 13.3 in (50.8 × 33.9 cm) |
| 48 MP | 8485 × 5657 | 28.3 × 18.9 in (71.8 × 47.9 cm) |
| 61 MP | 9566 × 6377 | 31.9 × 21.3 in (81.0 × 54.0 cm) |
The reassuring news is that megapixels matter far less than camera marketing implies. At 300 DPI a 12-megapixel phone photo prints a crisp 13.3 by 10 inches, comfortably covering the prints most people ever order. Note the shape change there: phones shoot 4:3, so 12 MP is 4000 × 3000 rather than the 4243 × 2829 in the 3:2 table above. Same pixel count, different rectangle, and that is why the two lines do not match. You only need 40- and 50-megapixel sensors if you crop hard or print genuinely large, which most of us never do. Chasing megapixels for ordinary prints is solving a problem you do not have.
Two things actually limit print size. The first is cropping: every time you cut into a frame you throw away pixels, so a heavy crop of a 24 MP shot might leave you with 8 MP of usable detail. The second is viewing distance, and it has a real formula behind it rather than a rule of thumb.
Required DPI ≈ 3,438 ÷ viewing distance in inches. That number comes from the resolving power of the human eye, which is roughly one arcminute. Work it through and the familiar advice falls out on its own:
| Viewed from | DPI you actually need |
|---|---|
| 10 in (held in the hand) | 344 |
| 12 in | 287 |
| 18 in | 191 |
| 24 in (2 ft) | 143 |
| 36 in (3 ft) | 96 |
| 60 in (5 ft) | 57 |
That is why 300 DPI became the standard for anything held at arm’s length, and why a billboard can be printed at 15 DPI and still look sharp from the road. What you cannot do is fake it: upscaling software invents pixels but not real detail, so a small file blown up large just looks soft no matter how clever the algorithm claims to be.
How we build and check this converter
This converter runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.