When you see the “TV Size” while shopping for a new TV, it’s important to know that this figure measures the diagonal distance between two corners of the screen. You can thank advertisers and marketers for the diagonal measurement: it allows them to promote a higher number than using the TV length or width, with the hope of increasing sales.
Popular TV Sizes & Dimensions
|TV Size (Diagonal)||Height||Width|
|45-inch TV||22 inches||39.2 inches|
|55-inch TV||27 inches||48 inches|
|65-inch TV||31.9 inches||56.7 inches|
|75-inch TV||36.8 inches||65.4 inches|
|85-inch TV||41.7 inches||74.1 inches|
|95-inch TV||46.6 inches||82.8 inches|
|100-inch TV||49 inches||87.2 inches|
|120-inch TV||58.8 inches||104.6 inches|
Unfortunately for consumers, we tend to visualize measurements in height and width, which is more practical for laying out space in a room, for example. Thankfully, some simple grade school math allows us to reverse engineer the mess made by TV marketers.
How to Calculate TV Height & Width
Televisions are rectangles, which can be divided into 2 right triangles, with the diagonal between them forming the hypotenuse.
The mathematical equation for determining the length of the sides of right triangles is called the Pythagorean Theorem. Assuming a 16:9 Aspect Ratio, we can find any TV’s Width and Height given a TV Size.
Width = (16/√337) * TV Size (Diagonal)
Height = (9/√337) * TV Size (Diagonal)
Understanding the Equation
The Pythagorean Theorem:
A2 + B2 = C2
The diagonal of the TV is the hypotenuse of the triangle:
A2 + B2 = (TV Size)2
The other two sides are the height and width:
(Height)2 + (Width)2 = (TV Size)2
Given the aspect ratio of modern televisions is 16:9, we can rephrase A2 + B2 in terms of one single variable that refer to eachother:
(16X)2 + (9X)2 = (TV Size)2
Solving for X we get:
X = √(TV Size)2/337
Explained in plain English, we can solve for X by squaring the TV Size, dividing by 337, and taking the square root of the result.
Two important notes!
This calculation can be used to determine the height and width of any TV when given the TV Size, but remember these two things:
- TV size refers to the diagonal of the screen, which doesn’t include any bezel or frame of the TV. The TV may be slightly taller or wider when considering any extra material beyond the screen itself.
- This calculation assumes a 16:9 aspect ratio, which is accurate for the vast majority of modern televisions, but there are some variations. A screen with a different aspect ratio (ex: 4:3) can apply the same concepts but must substitute accordingly.
List of TV Heights & Widths
Below we’ve listed the height and width of every possible TV Size from 45-inches to 120 inches based on the above calculations. Although manufacturers have a limited selection of TV Sizes available, this complete list will insure you can always find the dimensions of your TV, no matter the size.
TV Dimensions (Inches)
|TV Size||TV Height||TV Width|