PPI & Print Size Calculator

Convert between pixel dimensions, print size, and resolution (DPI/PPI). Enter pixels and a DPI to get the physical print size in inches, centimetres, and millimetres, plus the megapixel count and diagonal; enter a physical size and DPI to get the pixels needed; or enter pixels and a diagonal to find the PPI of a display. Pairs with the Aspect Ratio Calculator. Everything runs locally in your browser.

Width px Height px DPI

Print width in inches = pixels / DPI; one inch is 25.4 mm. Megapixels = (width × height) / 1,000,000. Diagonal in inches = √(w² + h²) / DPI; PPI of a display = √(w² + h²) / diagonal. Pixels from a physical size = round(inches × DPI). Everything runs locally — nothing leaves your browser.