How to Calculate Screen Size
What is Screen Size?
A screen size calculator converts a display's diagonal size (how screens are marketed) into actual width and height dimensions using the aspect ratio. The stated diagonal is the corner-to-corner measurement — a 55-inch TV is not 55 inches wide.
Formula
Step-by-Step Guide
- 1Width = Diagonal × cos(arctan(height_ratio / width_ratio))
- 2Height = Diagonal × sin(arctan(height_ratio / width_ratio))
- 3For 16:9: Width = Diagonal × 0.8721, Height = Diagonal × 0.4906
- 4Area = Width × Height
Worked Examples
Frequently Asked Questions
What is Screen Size?
A screen size calculator converts a display\. Use this calculator for accurate, instant results.
How accurate is the Screen Size calculator?
The calculator uses the standard published formula for screen size. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Screen Size calculator use?
This calculator works with inches, watts. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Screen Size calculator use?
The core formula is: Width = Diagonal × cos(arctan(height_ratio / width_ratio)). Each step in the calculation is shown so you can verify the result manually.
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