Screen size and viewing distance calculator
How big the screen should be for the room, how small the text can go, when 4K is worth paying for, and how close people can stand to an LED wall.
The image needs to be about 100 cm tall, a diagonal of 80 inches; 86 inches is the next commercial size up.
about 50 px at 1080p, 101 px at 4K, on a 86-inch screen
closer than this, viewers start to see the pixels
pay for 4K only if people stand closer than the 1080p figure
LED wall, 2.5 mm pixel pitch
one metre per millimetre of pitch, the practical rule
ten feet per millimetre, the conservative rule
or 2.0 mm for detailed content
Commercial sizes, landscape 16:9
| Diagonal | Width × height | Text, farthest viewer | Mixed | Video |
|---|---|---|---|---|
| 32" | 71 × 40 cm | 1.6 m | 2.4 m | 3.2 m |
| 43" | 95 × 54 cm | 2.1 m | 3.2 m | 4.3 m |
| 50" | 111 × 62 cm | 2.5 m | 3.7 m | 5.0 m |
| 55" | 122 × 68 cm | 2.7 m | 4.1 m | 5.5 m |
| 65" | 144 × 81 cm | 3.2 m | 4.9 m | 6.5 m |
| 75" | 166 × 93 cm | 3.7 m | 5.6 m | 7.5 m |
| 86" | 190 × 107 cm | 4.3 m | 6.4 m | 8.6 m |
| 98" | 217 × 122 cm | 4.9 m | 7.3 m | 9.8 m |
| 110" | 244 × 137 cm | 5.5 m | 8.2 m | 11.0 m |
Rules of thumb, not a standard: image height of one quarter, one sixth or one eighth of the farthest viewing distance; one inch of text per ten feet; pixels become visible at about 3.2 image heights for 1080p and 1.6 for 4K. Check the panel's own spec for brightness and duty cycle, which matter as much as size.
Choosing the screen
Size follows the farthest viewer, not the wall. Measure from the screen to the last person who still needs to read it, decide how closely they have to read (a menu is read; an advert is glanced at), and the tool gives the image height that works, rounded up to a panel you can buy. Portrait screens use the same rule on the long side.
Resolution is the number most people overpay for. Beyond about three image heights, 1080p and 4K look identical to a normal eye; 4K earns its price on a big panel in a small room, or on a video wall people walk up to. Brightness is the number people underpay for: a screen behind glass in daylight needs far more than one in a corridor. Our pages on LCD displays and LED displays cover both, and the screen sizes and formats guide goes through orientation and content layout.
For an LED wall the question is pixel pitch. The practical rule is a metre of viewing distance per millimetre of pitch; installers quoting for text-heavy content use ten feet per millimetre. Cost rises steeply as pitch falls, so buy the coarsest pitch the room allows.
Questions
- How is the recommended size calculated?
- From the farthest viewer. The image height should be at least one quarter of that distance for text people must read, one sixth for mixed content, and one eighth for video and pictures. The diagonal follows from the height and the aspect ratio, and the tool rounds up to the next commercial size.
- How small can the text be?
- The signage rule is one inch of letter height for every ten feet of viewing distance, about one centimetre per 1.2 metres. The tool turns that into a height in centimetres and in pixels on the recommended screen, so a designer can set a minimum font size.
- When does 4K matter?
- Only when viewers stand close. A person with normal sight starts to see individual 1080p pixels at about 3.2 times the image height, and 4K pixels at about 1.6 times. Beyond that, 1080p and 4K look the same, and the tool gives both distances for the recommended screen.
- How close can people stand to an LED wall?
- The practical rule is one metre per millimetre of pixel pitch: a 2.5 mm wall reads well from 2.5 m. The conservative rule used for detailed content is ten feet per millimetre, about three metres per millimetre. The tool gives both.
The screen is the expensive part. The software need not be.
Once the panel is on the wall, easyCMS runs it for 49 €, paid once. Windows, Android, LG webOS and Samsung Tizen.