What size TV for my room?
Measure from the TV wall to your eyes on the sofa, then pick a size that fills a comfortable part of your view.
Checked against UK retailer and maker guides on 21 October 2026.
Viewing distance chart
| TV size (16:9) | Screen width | Closest: 40° (THX) | Furthest: 30° (SMPTE) |
|---|---|---|---|
| 32 inch | 0.71 m | 1.0 m | 1.3 m |
| 43 inch | 0.95 m | 1.3 m | 1.8 m |
| 50 inch | 1.11 m | 1.5 m | 2.1 m |
| 55 inch | 1.22 m | 1.7 m | 2.3 m |
| 65 inch | 1.44 m | 2.0 m | 2.7 m |
| 75 inch | 1.66 m | 2.3 m | 3.1 m |
| 85 inch | 1.88 m | 2.6 m | 3.5 m |
What the two figures mean
Both measure how wide the screen looks from your seat. SMPTE (the Society of Motion Picture and Television Engineers) recommends a 30° field of view; THX recommends about 40° for an immersive, cinema-like picture (Smart Home Cinemas). Sit between the two figures. Closer than the 40° figure can be uncomfortable; further than the 30° figure and the screen loses impact.
THX’s shortcut: divide the screen size by 0.835 to get the ideal maximum distance in inches. For a 3 m viewing distance that suggests about 99 inches; SMPTE’s 30° says about 73 inches is enough (Smart Home Cinemas).
4K and closer seats
Smart Home Cinemas, quoting Kaleidescape, says 2K is fine at 30° and 4K is worth it at 40°.
Check the TV’s width (not the diagonal) against your wall or TV unit: a 65 inch TV is about 1.44 m wide.
Questions
What size TV for a 2.5 m viewing distance?
About 61 to 82 inches. At 2.5 m a 61 inch screen fills 30° of your view (SMPTE) and an 82 inch screen fills 40° (THX), using the same geometry as Smart Home Cinemas. Of common sizes, 65 and 75 inch fall inside that range.
How far should I sit from a 55 inch TV?
About 1.7 to 2.3 m (Smart Home Cinemas’ THX and SMPTE figures).
How far should I sit from a 65 inch TV?
About 2.0 to 2.7 m.
Where these numbers come from
Checked 21 October 2026. Makers round sizes differently, so always check the dimensions on the product you're buying.