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Pixel Density calculator

Pixel density (PPI) tells you how sharp a screen is. Enter the resolution and screen size to find pixels per inch.

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Pixel Density

PPI = √(w² + h²) / d · Screen Resolution

PPI = √(w² + h²) / diagonal  |  Pixels per Inch

About the Pixel Density calculator

Pixel density (PPI) tells you how sharp a screen is. Enter the resolution and screen size to find pixels per inch.

How to use the Pixel Density calculator

  1. Enter the Width (px) and Height (px) of the screen resolution.
  2. Enter the Diagonal (inches).
  3. Press Calculate.

Formula and method

PPI = √(width² + height²) ÷ diagonal in inches

Worked example

A 1920 × 1080 screen that is 27 inches across the diagonal has about 81.6 PPI. The same resolution on a 24-inch screen is about 91.8 PPI.

Tips

  • Phones are typically above 400 PPI, monitors between 90 and 160.
  • Higher PPI makes text and images look sharper at the same viewing distance.

Frequently asked questions

Is higher PPI always better?
Beyond a certain point, your eyes cannot see the difference at normal viewing distance.