What does this tool do?
Print size depends on pixel dimensions and the resolution the printer is asked to use. This calculator divides pixels by DPI to give the physical width and height, plus a comparison at 150 DPI.
The Formula
Print width = Pixel width ÷ DPI; print height = Pixel height ÷ DPIFrequently Asked Questions
How many pixels do I need for an 8 × 10 inch print at 300 DPI?
Multiply each side by 300: 8 × 300 = 2,400 pixels and 10 × 300 = 3,000 pixels, so 2,400 × 3,000 pixels, or about 7.2 megapixels.
Does DPI change the number of pixels?
No. DPI only changes how large those pixels are printed. Resampling can add pixels, but it cannot recover detail that was never captured.