If you’re in the market for a new TV, you might be looking at the sizes and have no idea what size you want besides one that fits inside your house and your budget. What’s the differences between a 42″ and a 56″ TV? Is there such a thing as a TV that’s too big?
There are two sites that can help answer your questions. The first, TV Size Matters, allows you to picture a TV of different sizes on your wall. You just upload a picture of your wall and set the scale. For example, you could measure the height of a set of speakers or a window that are in the picture and tell the site how tall that is. Once you have the picture up and the scale set, you can use the slider on the right to increase the size of the TV over your picture. After using this, you’ll have a pretty good idea how different sized TVs will look in your place.
While the previous approach looked at the aesthetics of how different sized TVs would look, the next covers how big of a TV you should have based on how far you are from the TV. One general rule of thumb to calculate how far you should be sitting away from the TV is to multiply the diagonal width of the TV by 2.5.
D(istance) = W(idth) * 2.5
Therefore, the diagonal width of your TV should be the distance from your couch to the TV divided by 2.5.
W(idth) = D(istance) / 2.5
So if your couch is 6 feet away from your entertainment center, you should be getting a…
10 feet * 12 inches/foot = 120 inches /2.5 = 48 inches
A 48 inch TV. (TVs and monitors are measured diagonally, from corner to corner.)
Manufacturers seem to like the 2.5 rule but others recommend a lower number. THX also has this guide on their site for their 40 degree rule for an immersive experience. Wikipedia also has a fewer other methods of calculating optimum distance and ranges recommended by manufacturers.
Why do all that pesky math though when there are online calculators that can do it for you? One such example, is able to adapt quite a bit to the information that you do have to calculate the distance.