What Size TV Should You Buy? A Room-by-Room Guide

Screen size is usually the first decision, but "biggest you can afford" isn't the right rule for every room. Sit too close to an oversized TV and you'll notice individual pixels or find yourself turning your head to see the edges; sit too far from a small one and the detail gets lost entirely. Here's how to actually work it out.

Start with viewing distance, not the TV

Measure the distance in centimetres from where you normally sit to where the TV will go. As a rough guide for 4K sets, divide that distance by 1.5 to get a sensible screen size in inches, a 3 metre viewing distance points you toward something around 65 inches. Older 1080p TVs need more distance for the same size before pixels become visible, so divide by 1 to 1.2 instead if you're not buying 4K.

What each size range suits

Under 43 inches works well for bedrooms, kitchens, small snugs, or as a second TV. 43 to 55 inches suits most living rooms with 2.5 to 3.5 metres to the sofa, which is why it's the most common size sold in the UK. 55 to 65 inches fits larger living rooms, gaming setups, and film nights where the seating is 3.5 metres or more back. 65 inches and above is for big open-plan rooms or a dedicated media room, anywhere the sofa genuinely sits that far away.

Resolution changes the maths

4K and 8K TVs pack more pixels into the same screen size, so you can sit closer to a bigger screen before any softness becomes visible. If you're buying a large TV for a smaller room, prioritise 4K, now standard on most sets above 43 inches, over a cheaper Full HD equivalent.

Don't forget the cabinet or wall space

Measure your TV unit or the available wall space before you fall for a bigger size than actually fits. Check the stand's footprint as well as the screen's width if you're not wall-mounting it, some stands are noticeably wider than the panel itself.

The short version

Measure your sofa-to-TV distance first, then match the size to that distance and your chosen resolution, not the other way round. A screen that's too big for the room is just as disappointing as one that's too small.

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