Tech
DPI Calculator
A DPI calculator estimates pixel density (DPI/PPI) by comparing pixel resolution against physical diagonal size in inches.
Quick answer
Enter pixel width and height.
What this tells you
- •Enter pixel width and height.
- •Enter physical diagonal size in inches.
- •Get DPI/PPI estimate and implied physical width/height.
How to Use
- 1Enter display pixel width and pixel height.
- 2Enter diagonal size in inches.
- 3Calculate to view estimated DPI/PPI and print-size assumptions.
How It Works
Formula
DPI = sqrt(widthPx^2 + heightPx^2) / diagonalInchesThe tool computes pixel diagonal and divides by physical diagonal inches to estimate density.
Calculation note: values are processed in the order shown above, using the current input units.
Worked Examples
1080p on 24-inch display
Width1920
Height1080
Diagonal24
Result~91.79 DPI
Common mistakes
- Confusing DPI with image export DPI metadata
- Using incorrect diagonal size
- Mixing PPI and printer DPI context
Frequently Asked Questions
For display density estimation, DPI and PPI are often used interchangeably.