Formula and method
distance = screen width ÷ (2 × tan(field of view ÷ 2))
This geometry keeps the screen at a chosen visual angle. It does not diagnose eyesight or guarantee comfort, so the result should be treated as a starting range.
Assumptions and limits
- Distance is measured from the viewer’s eyes to the screen plane.
- The viewer is centered horizontally.
- Personal eyesight, subtitles and room layout can change the preferred distance.
Worked examples
55-inch 16:9 TV
The screen is 47.94 inches wide. A 30° field of view gives about 7.45 ft; a 40° field of view gives about 5.49 ft.
32-inch 16:9 monitor
The 27.89-inch width gives about 4.34 ft at 30°, or 3.19 ft at 40°. Desk use may call for an even wider field of view.
Example 16:9 viewing distances
| Screen | 30° relaxed | 40° immersive |
|---|---|---|
| 43 in | 5.83 ft / 1.78 m | 4.29 ft / 1.31 m |
| 55 in | 7.45 ft / 2.27 m | 5.49 ft / 1.67 m |
| 75 in | 10.17 ft / 3.10 m | 7.48 ft / 2.28 m |
Frequently asked questions
Which field of view should I choose?
Use 30° for a relaxed mixed-use setup and 40° for a more immersive cinema-like image. Then adjust for comfort.
Does 4K change the ideal distance?
Higher resolution can support closer viewing before individual pixels become visible, but field of view still controls image immersion.