Screen Dimensions Calculator
Results
Enter values and click calculate.
How the Screen Dimensions Calculator Works
A screen's diagonal measurement is the standard size you see in product listings, but it doesn't directly tell you the exact width and height. This calculator converts a diagonal size and aspect ratio into real-world screen dimensions, then optionally computes pixel density when resolution is provided.
The Math Behind Screen Dimensions
The screen's width and height are derived from the diagonal using the aspect ratio. If the aspect ratio is W:H, then:
- Diagonal factor = √(W² + H²)
- Width (inches) = Diagonal × (W / Diagonal factor)
- Height (inches) = Diagonal × (H / Diagonal factor)
The calculator then converts inches to centimeters (1 inch = 2.54 cm) and computes surface area in both square inches and square centimeters.
Pixel Density (PPI)
If you enter resolution, the calculator estimates pixels per inch (PPI). PPI is calculated from the pixel diagonal divided by the screen diagonal:
- Pixel diagonal = √(Resolution Width² + Resolution Height²)
- PPI = Pixel diagonal / Diagonal (inches)
Realistic Example
A 27-inch monitor with a 16:9 aspect ratio has a width of about 23.53 inches and a height of about 13.24 inches. If the resolution is 2560×1440, the pixel diagonal is about 2937 pixels, resulting in roughly 109 PPI. This helps compare sharpness across displays of different sizes.
Common Use Cases
- Choosing a monitor size that fits a desk or wall mount
- Comparing physical screen size versus resolution and sharpness
- Calculating display area for digital signage layouts
- Matching screen size across multi-monitor setups