Free tool · runs in your browser
Photo Print Size Calculator
Enter the pixel dimensions of the file and the DPI you plan to print at. Crop before measuring.
Print shops may crop to a standard paper ratio. Compare the aspect ratio with the paper before ordering.
The arithmetic
Inches = pixels ÷ DPI. Centimetres = inches × 2.54. Megapixels = width × height ÷ 1,000,000. The aspect ratio is width ÷ height, shown as a decimal.
Common paper ratios
A 3:2 camera frame matches 6×4 inch prints. A 4:3 frame matches most phone sensors and crops slightly at 3:2. A 5:4 or square print crops more, so check the crop before ordering.
Frequently asked questions
Is 300 DPI per inch or per centimetre?
Per inch. If a shop asks for pixels per centimetre, multiply the DPI by 2.54.
Does the file’s embedded DPI matter?
The embedded value is metadata. The pixel dimensions are what limit the print. The calculator uses pixels and your chosen print resolution.
How large can I print at 150 DPI?
Twice the linear size of the 300 DPI result. Set the DPI field to 150 and read the width and height.