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Screen Size Calculator

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Area
Pixel Density
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What Your Result Means

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

Method & review

MethodologyHow we calculate this Reviewed & Updated2026-04 Next review2027-04

Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.