DPI Calculator
Pixels, print size, DPI โ enter two, get the third with a verdict.
About this calculator
Three ways round the same equation: check what DPI your image prints at a given size, find the pixels needed for a size at target quality, or find the largest clean print your image allows. Every answer carries a plain-language verdict calibrated to real viewing distances.
DPI demystified in one paragraph
DPI is just pixels รท inches โ there is no magic in the number. 300 is the print-shop standard because eyes at reading distance resolve no finer; required DPI FALLS with viewing distance, which is why a 150-DPI poster and a 30-DPI billboard both look sharp from where people actually stand. The myth this tool exists to bury: the "72 DPI" stamped in a file's metadata changes nothing on screens and nothing about the pixels โ monitors display pixels 1:1, and print software recalculates from actual dimensions. What matters is only the pixel count against the physical size. Hit a pixel target with the resizer, check a file's true dimensions in the EXIF viewer, and print-layout passport photos with the print sheet.
Frequently asked questions
How many pixels do I need for a sharp A4 print?
A4 is 8.27 ร 11.69 inches: at 300 DPI that's 2480 ร 3508 pixels โ about 8.7 megapixels. Any modern phone clears it.
Is 300 DPI always necessary?
Only for prints viewed at arm's length. 200 DPI looks excellent framed on a wall; 150 works for posters; billboards run 15-30. Distance is the variable everyone forgets.
Does changing the DPI value in a file improve quality?
No โ the metadata DPI is just a suggested print size; the pixels are unchanged. Quality comes from pixel count versus physical size, which is exactly what this calculator computes.
What DPI are phone photos?
The question needs a size: a 12 MP photo (4032 ร 3024) prints 13.4 ร 10 inches at 300 DPI, or A3 at ~240. Pixels are the currency; DPI is just the exchange rate.