About this tool
A photo that looks perfectly sharp on a screen can turn out blurry, or absurdly small, once it's printed — because a pixel is not a fixed physical size. DPI (dots per inch — or PPI, pixels per inch, for the source image) tells a printer how densely to pack those pixels onto paper: a 3600×2400px photo prints at 12×8in at 300 DPI, the density long considered the sweet spot for photo-quality prints, but the exact same file spread across a page at 72 DPI would print nearly 50×33in — the same pixels, a wildly different real-world size.
This calculator handles both directions of that conversion instantly, entirely in your browser. Enter an image's pixel dimensions — or drop the file in below and let it read them automatically, without uploading or modifying the image — together with a DPI, to see the physical print size in inches and centimeters. Or enter the physical size you want to print at plus a target DPI to see the pixel dimensions the file needs to have. Reach for 300 DPI for photos and documents viewed up close, 150 DPI for draft prints or large banners viewed from a distance, and the lower legacy values (72/96) only when sizing something meant for a screen rather than paper.
Frequently asked questions
What DPI should I use for professional photo printing?
300 DPI is the widely-used industry standard for high-quality photo and document printing viewed at normal reading/handling distance — it's dense enough that individual dots aren't perceptible to the human eye. Lower DPI (150) can look acceptable for large-format prints viewed from farther away (posters, banners), since viewing distance naturally reduces the eye's ability to resolve fine detail; higher DPI (600) is mainly useful for very fine detail work or when the print might be examined up close.
Does uploading my image for auto-fill send it anywhere?
No — the optional image upload (in the print-size calculator's pixel-dimensions section) only reads the file's width and height locally in your browser to fill in the number fields; the image data itself is immediately discarded afterward and never leaves your device. This convenience shortcut exists purely so you don't have to manually look up and type in an image's pixel dimensions.