TV Size and Distance Calculator - Best Screen for Your Room

About the TV Size and Distance Calculator

Choosing a television is mostly about one number: its size. Too small for the room and the picture feels distant and detail is lost; too large for where you sit and you are turning your head to follow the action. With 4K screens now common and large sizes much cheaper than they used to be, many people find the ideal screen is bigger than they would have guessed.

This TV size and distance calculator works both ways. Enter your screen size to find the best viewing distance, or enter your seating distance to find the best screen size. It uses the viewing-angle guidelines used by film and television engineers, gives the screen's width and height, and shows how close you can sit before you see individual pixels on a 4K or 1080p screen.

How to Use the TV Size and Distance Calculator

Choose whether you know the TV size or your seating distance.

Enter the screen size in inches, measured diagonally, or your viewing distance from your eyes to the screen.

Choose whether distances are in feet or metres.

How the Distance Is Worked Out

For a standard 16:9 screen:

  width     =  diagonal × 0.8716
  height    =  diagonal × 0.4903
  distance  =  width ÷ (2 × tan(angle ÷ 2))

  30° (everyday viewing):  distance ≈ width × 1.87
  40° (cinema feel):       distance ≈ width × 1.37

  closest without seeing 4K pixels  =  width ÷ 3,840 ÷ tan(1 arcminute)

Step-by-Step Example

A 65-inch TV.

  Width:     65 × 0.8716                 =  56.7 in  (height 31.9 in)
  40°:       56.7 ÷ (2 × tan 20°)        =  77.8 in  =  6.5 ft
  30°:       56.7 ÷ (2 × tan 15°)        =  105.7 in =  8.8 ft
  4K:        pixels blend at 4.2 ft or farther; 1080p at 8.5 ft

Sitting 9 feet (108 inches) away.

  30°:       108 × 2 × tan 15° ÷ 0.8716  =  66 in
  40°:       108 × 2 × tan 20° ÷ 0.8716  =  90 in

Viewing Angle Guidelines

30 degrees comes from the SMPTE, the society of film and television engineers, as a minimum for a satisfying picture. It suits general viewing: news, sport, and watching with the lights on.

40 degrees is the THX recommendation for a cinema-like experience, where the screen fills more of your vision. It suits films and games, and dedicated media rooms.

Anywhere between the two gives an immersive picture that is still comfortable. Much closer than the 40-degree distance and you have to move your eyes and head to see the edges; much farther than 30 degrees and the screen feels small.

Resolution and Distance

Human eyesight can resolve detail down to about one arcminute — one-sixtieth of a degree. When each pixel on the screen subtends less than that angle from where you sit, individual pixels blend into a smooth picture. On a 65-inch 4K screen, that happens from about 4.2 feet away; on a 1080p screen of the same size, from about 8.5 feet. This is why 4K makes the biggest difference on large screens viewed from close up: at typical living-room distances, a small 4K TV looks much like a 1080p one.

Screen Size and Your Room

The calculated range is a guide, not a rule. Measure the space where the TV will go, including the width of the frame and stand, which can add a few inches. Think about the room's layout: a sofa against the far wall sets the distance, and a very bright room may favour a slightly larger, brighter screen. Many people sit farther from the screen than the ideal and choose a size by eye in the shop, where screens look smaller than they do at home. Marking the screen's width and height on the wall with tape is a good way to check a size before buying.

Mounting Height

The centre of the screen should ideally be at about eye level when seated, often around 40 to 42 inches, or roughly a metre, from the floor. Mounting a TV high above a fireplace forces you to look up, which becomes uncomfortable over a long film.

Common TV Sizes

Size	Width × height	Everyday distance (30°)	Cinema distance (40°)
43 in	37.5 × 21.1 in	5.8 ft	4.3 ft
55 in	47.9 × 27 in	7.5 ft	5.5 ft
65 in	56.7 × 31.9 in	8.8 ft	6.5 ft
75 in	65.4 × 36.8 in	10.2 ft	7.5 ft
85 in	74.1 × 41.7 in	11.5 ft	8.5 ft

Screens for Gaming and Computers

Gamers and people using a TV as a computer monitor usually sit much closer than the living-room figures, often 2 to 4 feet from a desk. At that distance a smaller screen, or a very high resolution, avoids visible pixels and excessive head movement. For competitive gaming, many players prefer a screen that fits comfortably within their central vision, so they can see the whole picture at once without moving their eyes away from the action in the middle of the screen.

Understanding Your Result

Recommended gives the best distance range for your TV, or the best size range for your seat.

Cinema feel gives the distance or size for a 40-degree view.

Everyday viewing gives the distance or size for a 30-degree view.

Screen size gives the screen's width and height.

Resolution shows how close you can sit before pixels are visible.

When Should You Use This Calculator?

Buying a new TV.

Planning a living room or home cinema.

Choosing a projector screen size.

Deciding between 4K and 1080p.

Checking a TV will fit a wall or cabinet.

Common Mistakes

Choosing a TV too small for the room.

Measuring distance from the wall instead of your eyes.

Forgetting the frame and stand when checking space.

Paying for 4K on a small screen viewed from far away.

Mounting the TV too high.