TV Viewing Distance Converter

Optimal viewing distance depends on screen size and resolution. Higher resolution allows you to sit closer without seeing pixels.

THX recommendation (for cinematic experience):

• Viewing angle of about 40 degrees

Society of Motion Picture and Television Engineers (SMPTE):

• Minimum 30-degree viewing angle

Resolution-based formulas: The minimum distance where pixels are not visible to normal vision (20/20):

• 1080p: Distance = screen height × 3.0
• 4K (2160p): Distance = screen height × 1.5
• 8K (4320p): Distance = screen height × 0.75

Screen height from diagonal:

• Height = diagonal × 0.4903 (for 16:9 screens)
• Width = diagonal × 0.8716 (for 16:9 screens)

Example for 55" TV (screen height 27.0 in / 68.5 cm):

All measurements assume a standard 16:9 aspect ratio display.

Where the “farthest” column comes from

The closest figure is the pixel-visibility limit above. The farthest is simply the point at which the next resolution down would look identical, so you have stopped getting anything for the extra pixels. Each row’s maximum is the row below it turned upside down: 4K stops paying its way at 3.0 screen heights, which is exactly where 1080p starts, and 1080p stops at 4.6, which is about where 720p starts. Sit further back than the number in the right-hand column and you have bought resolution you cannot see.

Viewing angle, which is the other way to size a room

Those two come from geometry rather than from eyesight: the distance at which a 16:9 screen fills a given slice of your vision. For the same 55 inch set that is 1.67 m (5.5 ft) for THX and 2.27 m (7.4 ft) for SMPTE, and they sit inside the 4K band above, which is the point. A screen big enough to feel like a cinema is also close enough to justify the pixels.

The counterintuitive takeaway from these numbers is that most people sit too far away to see what they paid for. 4K only looks sharper than 1080p if you’re close enough for your eye to resolve the extra pixels, and on a 55-inch set that means roughly within seven feet. Sit across a large living room and a 4K and a 1080p set of the same size look identical, because the detail is finer than your eye can pick out at that range. The practical fix is almost always a bigger screen, not a higher resolution number.

The other way to think about it is field of view. Cinemas and the THX guideline aim for the screen to fill about 40 degrees of your vision, which is what makes a film feel immersive rather than like watching a postcard across the room. That’s why “what size TV should I buy” really depends on your sofa distance: measure how far you actually sit, then size up until the screen fills that angle. Almost nobody regrets going bigger; plenty of people regret buying a sharp TV they sit too far away to appreciate.