Print, Paper & Photo Sizes

Print sizes are physical, so they need a resolution before they mean anything on a screen. A4 is 210 × 297 mm: that is 2,480 × 3,508 pixels at 300 DPI, but only 794 × 1,123 at 96 DPI. The right choice depends on how close the print will be viewed.

Each preset sets the physical width and height. The page converts it to pixels at 72, 150 and 300 DPI, names the standard when there is one (ISO A-series, US Letter, common photo sizes) and checks whether a typical phone photo has enough pixels.