Screen Size Calculator
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What Your Result Means
- Width & Height: The actual physical dimensions of the visible screen area in inches and centimeters.
- Area: Total screen real estate in square inches; useful for layout planning and judging overall screen size.
- Pixel Density (PPI): Pixels per inch measures sharpness; typically 90–110 ppi looks good on desktop monitors, while 300+ ppi is smartphone-grade clarity.
- Aspect Ratio: The proportional width-to-height relationship; wider ratios (21:9, 32:9) create panoramic displays for multitasking or gaming.
- Display Fit: Compare the calculated width and height to your available wall or desk space to confirm your screen will fit comfortably.
How This Calculator Works
This calculator uses the Pythagorean theorem to decompose a diagonal measurement and aspect ratio into width and height. Given a diagonal D and aspect ratio r (e.g., 16:9 = 1.778), the width is calculated as D / √(1 + 1/r²), and height follows from height = width / r. These dimensions are then converted to centimeters (1 inch = 2.54 cm) and the area is computed. When you provide a resolution (e.g., 1920 × 1080), the calculator also derives pixel density by calculating the diagonal pixel count and dividing by the physical diagonal in inches.
Quick Questions
What if my monitor's diagonal isn't labeled?
Check the manufacturer's spec sheet (usually available online); the diagonal is always listed. If it's not, you can measure the screen corner-to-corner diagonally with a measuring tape.
Does PPI affect picture quality?
Yes. Higher PPI reduces visible pixelation; 110 ppi is crisp at typical monitor viewing distance, while 70 ppi may show jaggedness up close.
Can I use this for ultrawide gaming monitors?
Absolutely. Select 21:9 or 32:9 to get accurate width and height for ultrawide displays designed for immersive gaming or productivity setups.
Why does my monitor's bezel reduce the visible area?
The diagonal specification refers to the visible panel only, not the black border. This calculator shows only the usable screen dimensions.
Sources
- Wikipedia: Display Size — Standard diagonal measurement and aspect ratio conventions.
- VESA (Video Electronics Standards Association) — Display standards and certification reference.
- Wikipedia: Pixel Density — PPI and DPI standards across devices.