Screen PPI Calculator
Calculate a screen’s pixel density (PPI), dot pitch and physical dimensions from its resolution and diagonal size.
Your inputs
Results
Pixel density
91.79 PPI
- Dot pitch
- 0.2767 mm
- Screen width × height
- 20.92 × 11.77 in (53.1 × 29.9 cm)
- Total pixels
- 2,073,600
✓Exact calculation — rounded only for display
What this calculator does
PPI determines how sharp a screen looks at a given viewing distance.
Formula and method
PPI = √(width² + height²) ÷ diagonal; dot pitch = 25.4 ÷ PPI mm
Worked example
Calculated by this tool with its default inputs:
Inputs
- Horizontal resolution: 1920 px
- Vertical resolution: 1080 px
- Diagonal size: 24 in
Results
- Pixel density: 91.79 PPI
- Dot pitch: 0.2767 mm
- Screen width × height: 20.92 × 11.77 in (53.1 × 29.9 cm)
- Total pixels: 2,073,600
How to read the results
Higher PPI looks sharper; the benefit depends on viewing distance.
Assumptions and limitations
- Assumes square pixels.
Questions
What PPI is a 27-inch 4K monitor?
About 163 PPI.
Methodology and verification
- Result type
- Exact mathematical calculation (rounded only for display)
- Formula version
- 1.0
- Automated verification
- 3 reference and validation test cases, checked against independently computed values. The site cannot be built if any of them fail.
- Editorial review
- Awaiting human editorial review. The explanation was drafted with AI assistance; the formula and examples are verified by the automated tests above.
Privacy
Everything you enter is calculated in this browser and is not sent to Numerith or anyone else. Inputs are added to a share link only if you choose to include them. Privacy policy