Screen DPI Calculator
Find out the DPI (dots per inch, also known as PPI) of your screen by entering its resolution and diagonal size.
What is Screen DPI?
DPI (Dots Per Inch), often referred to as PPI (Pixels Per Inch), measures the pixel density of a screen. It tells you how many pixels fit within one inch of the display, giving you an idea of how sharp the screen looks.
Formula
DPI = √(Width² + Height²) ÷ Diagonal (inches)
This formula uses the Pythagorean theorem to calculate the total pixel diagonal and divides it by the screen’s physical diagonal size.
Example Calculation
Suppose you have a 1920 × 1080 resolution screen with a 15.6-inch diagonal:
Pixel Diagonal = √(1920² + 1080²) ≈ 2202 pixels
DPI = 2202 ÷ 15.6 ≈ 141 DPI
This means your laptop display has a pixel density of 141 DPI.
Typical Screen DPI Values
| Device Type | Typical DPI |
|---|---|
| Standard Laptop | 100–150 DPI |
| 4K Laptop / Monitor | 200–300 DPI |
| Smartphone | 300–500 DPI |
| Tablet | 200–300 DPI |
| Projector Screen | 50–150 DPI |
Why DPI Matters
- Clarity: Higher DPI means sharper, more detailed visuals.
- Print Matching: Ensures digital designs look correct when printed.
- Scaling: Affects how text and images are rendered on high-resolution displays.
- Gaming & Media: High DPI provides smoother, more immersive graphics.
FAQs
Is DPI the same as PPI?
For screens, DPI and PPI are used interchangeably. Technically, DPI is for print, while PPI is for displays.
Is higher DPI always better?
Higher DPI means sharper visuals, but it can also make interface elements smaller unless scaled.
What’s a Retina display?
Apple coined "Retina" for screens with DPI so high that the human eye can’t distinguish individual pixels at normal viewing distance.
Conclusion
Our Screen DPI Calculator quickly determines the pixel density of any display. Whether you’re setting up a laptop, TV, projector, or smartphone, knowing your screen’s DPI helps you understand its sharpness and suitability for different tasks.