How to Measure a Flat Panel TV

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How to Measure a Flat Panel TV
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While you might shop for a TV with the mantra bigger is better in mind, this isn't always the case. The right screen size depends on how far away you'll be viewing the screen from and the resolution of the set you're considering. Keep that in mind, though, that the actual screen size is a crucial aspect of finding the right set for your need. Screen size measurements are quoted as the diagonal measurement from one corner of the screen to the opposite corner. Learn more about TV sizes and how to measure for your ideal set before making a purchase to avoid disappointment.

Measure a TV Screen

All TV manufacturers use the same method when describing TV screen size. TV sizes are quoted as the diagonal distance from one corner of the screen to the opposite corner. So a 42-inch screen measures 42 inches from the top left corner to the bottom right corner of the screen (or the top right corner to the bottom left corner). Measure your TV with this in mind.

Get a tape measure and start from one corner of the screen. Hold the end in place as you stretch the tape measure out diagonally to the opposite corner. Read the measurement and make a note of it. It's best to measure TV sizes in inches because that's how they're quoted in the industry.

Viewing Distance and Screen Size

The TV screen size you need depends heavily on the distance from which you'll be viewing it. If the screen is too big for your space, you're likely to start seeing some pixelation of the images, which ruins the viewing experience. The key is getting a screen that's big enough to be easily visible but not so big that you can see the pixels when you're watching a program or movie.

The ideal relationship between viewing distance and TV screen size isn't precisely determined, but generally speaking, you want to sit between 1.5 and 2.5 times the screen size away from the TV. You can simplify this by just doubling the screen size to find the ideal viewing distance. For example, if you have a 42 inch TV, sitting 84 inches (7 feet) away from the screen provides optimal viewing.

There are some alternative formulas you can use to work out the ideal viewing distance. For example, Amazon recommends that you multiply the viewing distance in feet by 7.7 to find the ideal TV screen size in inches. Therefore, if you'll be sitting 7 feet away from the screen, the ideal screen size is 7 × 7.7 = 53.9 inches, so roughly 54 inches or less. However, using the simpler method – where your viewing distance should be double your screen size – is generally effective and much easier.

The Impact of Resolution

The resolution of the screen also affects the viewing distance because a sharper image is less likely to become noticeably pixelated when you get close to it. For a 4K ultra HD television, for example, the ideal viewing distance is between 1 and 1.5 times the size of the screen. So that same 42 inch TV set would be best viewed from between 42 and 63 inches away (3.5 feet to 5.25 feet), although larger distances would be OK.

The Importance of TV Dimensions

Screen size is measured diagonally, but the actual TV dimensions – as in, how tall and wide the whole unit is – are also crucial if you have a set amount of space for it. You can easily determine this because all you need to do is measure the physical space you have for the TV and measure the height and width of the set itself. However, if you forget to do this, you may run into problems when it comes to setting up your new TV.