Convert pixels to inches, centimetres and millimetres at a chosen DPI — and inches back to pixels — with common DPI presets and a custom option.
The conversion is pixels divided by DPI for inches; centimetres multiply inches by 2.54 and millimetres by 25.4. The reverse multiplies inches by DPI. DPI here means the density the pixels are mapped to — screens commonly use 96, print targeting uses 300, and older screen references use 72. Choosing a preset fills the DPI field; choosing Custom leaves the field free for any value, such as a printer specification.
How many pixels are in an inch? Exactly as many as the DPI setting: 300 pixels per inch at 300 DPI, 96 at 96 DPI. A pixel has no fixed physical size until a density is assigned.
Which DPI is right for print? 300 DPI at the final size is the standard target for sharp print. For screens, pixel dimensions alone usually matter more than the DPI figure.
Why do the centimetre and millimetre results differ in scale? They are the same length in different units: 1 inch is exactly 2.54 centimetres or 25.4 millimetres by definition.