DPI Calculator
DPI is just pixels divided by inches — which means the same image is 300 DPI in a wallet print and 72 DPI on a poster. Enter an image width and a print width to see its effective resolution (with a plain-English quality verdict), or set a target DPI to learn how many pixels that print size really needs.
Effective resolution: 300 DPI (print-quality)
You need 3000px across for 300 DPI at 10 inches.
The maths: DPI = pixels ÷ inches. A pixel count alone is never 300 DPI — DPI only exists once a physical print size is chosen. Screens, by contrast, just use pixels.
How to dPI Calculator
- Enter image width in pixels and print width in inches.
- Read the effective DPI and verdict.
- Or set a target DPI to get the required pixel width.
Frequently asked questions
Is 300 DPI always required?
It is the standard for close-viewed print (books, flyers). Posters viewed from a distance look fine at 100–150 DPI; billboards often run below 30. Viewing distance is what matters.
Can I just set an image to 300 DPI to improve it?
Changing the DPI number alone adds no pixels — printers would simply print it smaller. Real improvement needs more pixels (see the Print Size Calculator for what your pixels can cover).