How to use it
- Enter the screen size in inches (diagonal).
- Pick the aspect ratio (16:9 for TVs).
- Read the width, height and viewing distances.
- Or switch to Size from distance and enter how far you sit.
TV dimensions by screen size
TV sizes are the diagonal of the picture area. For a 16:9 screen, width = diagonal × 0.872 and height = diagonal × 0.490.
| Screen size | Width × height (screen) |
|---|---|
| 43 in | 37.5 × 21.1 in |
| 50 in | 43.6 × 24.5 in |
| 55 in | 47.9 × 27.0 in |
| 65 in | 56.7 × 31.9 in |
| 75 in | 65.4 × 36.8 in |
| 85 in | 74.1 × 41.7 in |
| 98 in | 85.4 × 48.0 in |
The TV itself is slightly larger because of the bezel, and taller on its stand; check the manufacturer's dimensions before buying a cabinet or wall niche.
How far should you sit?
Viewing distance guidelines are based on how much of your field of view the screen fills:
| Screen size | SMPTE 30° | THX 40° (theater feel) | 4K pixels visible closer than |
|---|---|---|---|
| 55 in | 7.5 ft | 5.5 ft | 3.6 ft |
| 65 in | 8.8 ft | 6.5 ft | 4.2 ft |
| 75 in | 10.2 ft | 7.5 ft | 4.9 ft |
| 85 in | 11.5 ft | 8.5 ft | 5.5 ft |
SMPTE recommends the screen fill at least 30° of your view; THX recommends about 36–40° for an immersive, cinema-like picture. The last column is the distance at which a person with 20/20 vision (1 arcminute acuity) can just start to see individual 4K pixels; for 1080p that distance roughly doubles.
What size TV for your room
Switch to Size from distance and enter how far your eyes are from the screen. Typical results for 16:9 TVs:
| Viewing distance | SMPTE 30° | THX 40° |
|---|---|---|
| 6 ft | 44 in | 60 in |
| 8 ft | 59 in | 80 in |
| 10 ft | 74 in | 100 in |
| 12 ft | 89 in | 120 in |
The calculator rounds to standard sizes you can buy. For a 4K TV, sitting at the THX distance is comfortable; with 1080p content, sitting a bit further back hides the pixel structure.
Comparing two TVs
Use Compare two TVs to see how much bigger the picture really is. Screen area grows with the square of the diagonal: a 75 in TV has about 33% more screen than a 65 in, although the diagonal is only 15% larger. The comparison shows the width, height and area of both.
You can also enter sizes in cm, and choose 21:9 (ultrawide monitors) or 4:3 (older TVs) to see how the same diagonal gives a different shape. 1 inch = 2.54 cm.
Frequently asked questions
How wide is a 65 inch TV?
The screen of a 16:9, 65 in TV is about 56.7 in wide and 31.9 in tall. With the bezel it's slightly larger.
How far should I sit from a 65 inch TV?
About 6.5 ft for an immersive THX-style picture, up to about 8.8 ft by the SMPTE 30° guideline.
What size TV for a 10 foot viewing distance?
About 75 in (SMPTE) to 100 in (THX). Many people choose 75–85 in at that distance.
Are TV sizes measured diagonally?
Yes. The size is the diagonal of the visible picture area, corner to corner.
How much bigger is a 75 inch TV than a 65 inch?
The diagonal is 15% larger, but the screen area is about 33% larger.
Last updated: November 12, 2026