Photo Print Size and DPI Calculator
Print size at a chosen resolution, and the resolution you would get at 30 cm wide.
Results
Printed width
33.87
cm
Print height
25.40
cm
Printed width
13.33
in
Megapixels
12.00
MP
Resolution
339
dpi
What this tool does
Three hundred dpi is the usual target for something held in the hand, but a poster read from two metres away looks perfectly sharp at 150 or less — viewing distance matters more than the number. The last result tells you what a 30 cm wide print would actually resolve at.
Formula
dpi = pixels ÷ inches
Variables
| Symbol | Meaning | Unit |
|---|---|---|
px | Image width in pixels | — |
py | Pixels (height) | — |
dpi | Resolution | — |
W | Printed width | cm |
H | Print height | cm |
WI | Printed width | in |
MP | Megapixels | MP |
D30 | Resolution | dpi |
Worked example
- Image width in pixels4000
- Pixels (height)3000
- Resolution300
- Printed width33.87 cm
- Print height25.40 cm
- Printed width13.33 in
- Megapixels12.00 MP
- Resolution339 dpi
Limitations
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
- The default values are typical reference figures, not measurements of your situation. Replace them with your own data whenever you have it.