Print size and DPI calculator
How big your photo can be printed, how sharp it will be on a given paper size, and how many pixels a print needs, worked out from the pixel dimensions alone.
Print size at 300 ppi
20 × 13.3 in
6000 × 4000 px · 24.0 megapixels
On 8 × 10 in paper
500 ppi
| Resolution | Good for | Largest print |
|---|---|---|
| Paper | Pixels for 300 ppi | Your image gives |
|---|---|---|
The arithmetic
Print size is pixels divided by resolution: inches = pixels ÷ ppi, and centimetres are inches × 2.54. A 6000 × 4000 pixel photo at 300 pixels per inch prints at 20 × 13.3 inches (50.8 × 33.9 cm). Going the other way, a print needs inches × ppi pixels on each side. Printers and labs often say dpi when they mean the image's ppi; here both mean pixels per inch of the print.
How much resolution is enough
What matters is detail at the distance people stand. The tables use 300, 240 and 150 ppi as reference points, from prints seen in the hand to larger prints seen from further away. As Wikipedia's pixel density article puts it, a print viewed close up can use the printer's limits, while a poster or banner seen from far away can use a much lower ppi; its example is a 1920-pixel-wide image stretched across a 48-inch banner, which gives only 40 ppi. If a paper size has a different shape from your photo, the table assumes you crop to fill it, and the preview shows what is cut.
Reading a photo's size
Choose or drop a photo and the calculator reads its width and height in your browser. The file is not uploaded and the picture is not stored.
Sources
- Wikipedia, Pixel density (PPI for printing, the banner example and viewing distance).
Questions
Does changing the DPI in my editor change the photo?
Only the print size tag. The pixels stay the same unless you resample, so a 6000-pixel-wide image prints at 20 inches at 300 ppi or 25 inches at 240 ppi.
Can I upscale for a bigger print?
Upscaling adds pixels but not real detail. It can smooth a print viewed up close, but it cannot recover detail the camera never captured.
Why does my 4 × 6 print crop the photo?
A 4 × 6 inch print has the 3:2 shape of most camera sensors, but 8 × 10 or A4 are squarer, so part of a 3:2 photo is cut to fill them.