Screen Size Calculator
Trying to figure out if that new 65-inch TV will fit on your media console, or how much extra desk space a 34-inch ultrawide monitor takes up? You are in the right place.
TV and monitor manufacturers always market displays using their diagonal size. But diagonal numbers don't tell you how wide or tall the display actually is in your room. Use the quick calculator below to instantly convert diagonal inches into exact physical width, height, and display area.
Calculate Display Dimensions
Calculated Dimensions
Compare Common Screen Sizes
Upgrading your display? See how much screen real estate you gain when jumping to a bigger size.
| Size Upgrade | Smaller Screen Area | Larger Screen Area | Screen Area Gain |
|---|---|---|---|
| 24" vs 27" Monitor | 246.2 sq in | 311.5 sq in | +26.5% More Viewable Area |
| 27" vs 32" Monitor | 311.5 sq in | 437.6 sq in | +40.5% More Viewable Area |
| 50" vs 55" TV | 1,068.1 sq in | 1,292.6 sq in | +21.0% More Viewable Area |
| 55" vs 65" TV | 1,292.6 sq in | 1,805.3 sq in | +39.7% More Viewable Area |
| 65" vs 75" TV | 1,805.3 sq in | 2,406.0 sq in | +33.3% More Viewable Area |
| 75" vs 85" TV | 2,406.0 sq in | 3,078.6 sq in | +28.0% More Viewable Area |
Note: Calculations assume standard 16:9 aspect ratio screens. TV bezels are not included in physical display dimensions.
Want a visual side-by-side screen comparison?
Compare any two TVs or monitors with live screen frames, exact width & height differences, and percentage area gains.
Common 16:9 Screen Dimensions
Standard height, width, and surface area measurements for popular TV and desktop monitor sizes.
| Screen Size | Width (Inches) | Height (Inches) | Display Area |
|---|---|---|---|
| 24" | 20.92" | 11.77" | 246.2 in² |
| 27" | 23.53" | 13.24" | 311.5 in² |
| 32" | 27.89" | 15.69" | 437.6 in² |
| 43" | 37.48" | 21.08" | 790.2 in² |
| 50" | 43.58" | 24.51" | 1,068.1 in² |
| 55" | 47.94" | 26.96" | 1,292.6 in² |
| 65" | 56.65" | 31.87" | 1,805.3 in² |
| 75" | 65.40" | 36.79" | 2,406.0 in² |
| 85" | 73.99" | 41.62" | 3,078.6 in² |
How to Use the Screen Size Calculator
Calculating display dimensions takes less than five seconds with these simple steps:
- Enter the Diagonal Size: Type in the screen size advertised on the box (e.g., 55 for a 55-inch TV).
- Choose Units: Select either Inches or Centimeters based on your preference.
- Select Aspect Ratio: Keep 16:9 for modern TVs and monitors, or pick 21:9 for Ultrawides and 16:10 for MacBooks.
- Add Resolution (Optional): Enter pixel counts (like 3840x2160) to see Pixel Density (PPI) and sharpness metrics.
That's it! The tool calculates physical height, physical width, total viewable area, and even renders an interactive live graphic of the screen proportions.
How Screen Size Math Works
Understand how Pythagorean geometry turns diagonal inches into precise screen width and height.
Because every screen forms a right triangle between its width, height, and diagonal line, we use the classic Pythagorean Theorem to solve for dimensions:
Width² + Height² = Diagonal²
When you know the aspect ratio (for example, W:H = 16:9), we express width in terms of height (Width = 16/9 × Height) and plug it directly into the equation:
Height = Diagonal / √( (Aspect Ratio)² + 1 )
Once height is known, multiplying it by the ratio gives you the exact screen width. Don't worry about keeping a calculator nearby though—our tool automates all of this math instantly!
Quick Formulas Summary
- 16:9 Width: Diagonal × 0.8716
- 16:9 Height: Diagonal × 0.4903
- 16:9 Area: Diagonal² × 0.4271
- Inches to CM: Inches × 2.54
Screen Size Calculator FAQ
Quick answers to helpful questions about TV and computer display measurements.
Why are screen sizes measured diagonally?
Measuring screens diagonally originated back in the early days of television when Cathode Ray Tubes (CRTs) were round. Manufacturers measured the diameter of the circular glass tube. Even as screens shifted to rectangular shapes, measuring diagonally stuck around as a unified marketing standard.
Does a 55-inch TV have double the screen area of a 32-inch TV?
No, it actually has almost three times more viewable screen area! Surface area grows exponentially, not linearly. A 32-inch TV has roughly 437 square inches of display space, while a 55-inch TV provides about 1,292 square inches.
Do screen size numbers include the outer bezel or frame?
No. Screen size calculations strictly measure the viewable display panel (where pixels actually light up). The plastic frame, metal trim, or TV stand adds extra physical width and height to the overall unit.
How far should I sit from my TV screen?
For modern 4K resolution TVs, a good rule of thumb is to sit at a distance equal to 1.0 to 1.5 times the diagonal screen size. For instance, with a 65-inch TV, sitting roughly 5.5 to 8 feet away delivers an immersive cinematic experience.