TV Size Calculator
Turn a screen's diagonal size into its real width, height and area for any aspect ratio, in inches and centimetres. Compare two TVs or monitors, including 16:9 and ultrawide screens, with a to-scale drawing.
How to use the TV Size Calculator
- Enter the diagonal of the screen and choose inches or centimetres.
- Choose the aspect ratio (most TVs are 16:9) or enter a custom ratio.
- Tick Compare and enter a second screen to see how much bigger or smaller it is.
- Press Calculate size to get width, height, area and the comparison.
- Use the table for the dimensions of common TV sizes.
Screen size formula
- Width = diagonal × a ÷ √(a² + b²)
- Height = diagonal × b ÷ √(a² + b²)
- Area = width × height; two screens of the same shape compare by (D₂ ÷ D₁)²
Multipliers for common shapes: 16:9 → width 0.8716 × D, height 0.4903 × D · 4:3 → 0.8 × D and 0.6 × D · 21:9 (64:27) → 0.9214 × D and 0.3887 × D · 16:10 → 0.8480 × D and 0.5300 × D.
16:9 TV dimensions chart
| Diagonal | Width | Height | Width × height (cm) | Area |
|---|---|---|---|---|
| 32" | 27.9 in | 15.7 in | 70.8 × 39.8 | 3.04 ft² |
| 43" | 37.5 in | 21.1 in | 95.2 × 53.5 | 5.49 ft² |
| 50" | 43.6 in | 24.5 in | 110.7 × 62.3 | 7.42 ft² |
| 55" | 47.9 in | 27.0 in | 121.8 × 68.5 | 8.98 ft² |
| 65" | 56.7 in | 31.9 in | 143.9 × 80.9 | 12.54 ft² |
| 75" | 65.4 in | 36.8 in | 166.0 × 93.4 | 16.69 ft² |
| 85" | 74.1 in | 41.7 in | 188.2 × 105.8 | 21.44 ft² |
| 100" | 87.2 in | 49.0 in | 221.4 × 124.5 | 29.67 ft² |
These are visible screen dimensions. Add the bezel (often 0.2–1 inch per side) and the stand height when planning a cabinet or wall space.
Frequently asked questions
How do you calculate TV width and height from the diagonal?
For an aspect ratio a:b, width = diagonal × a ÷ √(a² + b²) and height = diagonal × b ÷ √(a² + b²). For a 16:9 TV, √(16² + 9²) = 18.358, so width = diagonal × 0.8716 and height = diagonal × 0.4903.
What are the dimensions of a 65-inch TV?
The screen of a 65-inch 16:9 TV is about 56.7 inches wide and 31.9 inches tall (144 × 81 cm). The whole TV is slightly larger because of the bezel and stand, so check the manufacturer's spec sheet for the cabinet size.
How much bigger is a 65-inch TV than a 55-inch?
Screen area grows with the square of the diagonal: (65 ÷ 55)² = 1.397, so a 65-inch screen has about 40% more area than a 55-inch screen of the same aspect ratio.
Is the TV size measured with or without the frame?
TV and monitor sizes refer to the diagonal of the visible picture area only, measured corner to corner, not including the bezel.
Why does a 34-inch ultrawide look smaller than its diagonal suggests?
A wider aspect ratio puts more of the diagonal into width. A 34-inch 21:9 monitor is about as tall as a 27-inch 16:9 monitor (about 13.2 inches), just much wider. Use the comparison to see the equivalent diagonal at the same height.
What aspect ratio do TVs use?
Nearly all modern TVs are 16:9 (1.78:1). Older tube TVs were 4:3, many computer monitors are 16:10 or 21:9, and cinema films are often 1.85:1 or 2.39:1, which shows black bars on a 16:9 screen.