PPI Calculator
Find the pixel density of a screen from its resolution and diagonal size.
About PPI Calculator
The screen diagonal in pixels is divided by its diagonal length in inches to give pixels per inch, and 25.4 divided by PPI gives pixel pitch. PPI determines how dense and smooth a display looks, which matters when choosing monitors, phones and print-viewing sharpness.
Formula
PPI
PPI = diagonal pixels / diagonal inches; pitch = 25.4 / PPI
- pixel pitch
- Millimeters between pixel centers
Worked example
With the default values below, PPI Calculator returns PPI of 91.8. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Widthminimum 1 px
- 1,920 px
- Heightminimum 1 px
- 1,080 px
- Diagonalminimum 1 in
- 24 in
Results
- PPI
- 91.8
- Pixel Pitch
- 0.277 mm
- Sharpness
- Standard desktop density
Step by step
- 1Values used
- 2PPI
- 3PPI= 91.8
- 4Pixel Pitch= 0.277 mm
- 5Sharpness= Standard desktop density
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is PPI calculated?
PPI = diagonal pixels / diagonal inches; pitch = 25.4 / PPI The screen diagonal in pixels is divided by its diagonal length in inches to give pixels per inch, and 25.4 divided by PPI gives pixel pitch.
Why does PPI matter?
PPI determines how dense and smooth a display looks, which matters when choosing monitors, phones and print-viewing sharpness.
What values do I need to enter?
This calculator takes 3 inputs: Width, Height, Diagonal. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.