What size TV should you get?
Your seat, your size
Your seat
How to measure your distance
Tap the button. Stand the plate flat against the TV wall, walk back to your seat, and read the number at your feet.
With any tape measure: from your seat to where the screen will be.
Viewing preference
Home cinema
Dim the lights. A balanced movie-night view, with room to take in the whole frame.
Adjust viewing angle
20° sit back · 60° pull me in. 40° starting point
Enter a whole number from 20 to 60 degrees.
Recommended size
Nearest TV size for home cinema at 2.5 m · 40.4° of your view. Preferred fit.
TV · 40° · Preferred fit · example seat
Preferred listed sizes: 83–100″ · target 40°.
Illustrative preview
Common questions
Start with a distance guide: 2 m · 2.5 m · 3 m · 4 m · 8 ft · 10 ft.
How do I measure my viewing distance with an iPhone?
Tap Measure with your camera above. It opens a tape measure in augmented reality: stand the plate flat against the TV wall, walk back to your seat, and read the numbered mark at your feet. The tape is locked to true scale, so that mark is your seat-to-screen distance. Any physical tape measure works just as well.
What size TV does THX recommend for movies?
THX recommends a picture that fills about 40 degrees of your view, and that is the angle this calculator recommends for a cinematic home theater experience. A shorthand from the same math: divide your viewing distance by 1.2 to get the diagonal in the same units. From 2.5 m, about 98 inches, that is an 82 inch picture, which is why a screen that looks enormous in the shop stops looking enormous at home.
Is the recommended size too big for watching the news?
The recommendation is tuned for movies, sport and games: 40 degrees of view is a cinema seat, and immersion is what earns a big screen. News, talk shows and background TV are watched casually, often from across the room, and stay perfectly comfortable on a much smaller angle. For casual viewing, try News or TV shows above; every row shows the angle it fills and the sharpness it keeps from your seat.
When should you get a projector instead of a TV?
For the default 40° Home cinema target, past roughly 3.8 m (12.4 ft) of seating distance. More immersive targets reach projector sizes from closer seats. The largest TV this page recommends is 115 inches, the biggest size with sane pricing; larger sets exist, like Samsung's 130 inch Micro RGB, but at prices where a good projector beats them easily. From farther back no common TV reaches THX's cinematic 40 degrees, so this page switches its recommendation to a projector. A projected image is continuously sizable, so the page computes the exact diagonal that fills the view from your seat rather than snapping to a screen size. A 4K projector can exceed the conventional 60 PPD reference at these distances, but focus, light output, contrast and room control still affect visible detail.
Is 4K worth it at my viewing distance?
It depends on size and distance together. Use 60 central pixels per degree as a conventional comparison reference, not a universal visibility limit. From 2.5 m, a 4K panel stays above that line up to about a 126 inch diagonal, while 1080p crosses it at about 63 inches. The table above shows the sharpness every common size keeps at your distance.
Can a website read the distance out of AR automatically?
No. AR Quick Look, the iOS viewer this page uses, sends nothing back to the web page, and Safari on iOS does not support WebXR. The AR tape does the measuring at true scale; typing the one number back in is the manual step.
Every number on this page is computed from your distance with the DisplayMath screen size calculator. Free, no signup, runs in your browser. Nothing you enter leaves the page. Feedback? Email hello@displaymath.com or find us on Instagram. About · Privacy. © 2026 DisplayMath. All rights reserved.