Engineering
TV Size Calculator
Enter TV screen size and resolution to calculate screen dimensions and optimal viewing distance.
TV parameters
Resolution
Screen diagonal length
Viewing parameters
Optimal distance (THX 40°)
m
Minimal distance (pixels invisible)
m
TV Size Calculator: Correct Screen Size and Viewing Distance
When buying a TV, two critical questions arise: Is this screen size appropriate for my seating distance? And what resolution gives the best experience at that distance? This calculator answers both using THX and SMPTE standards.
Viewing Distance Standards
THX (40°)
Recommended distance for cinema-quality experience. Screen covers 40° of horizontal field of view. Distance = screen width / (2 × tan20°) ≈ 1.37× the width.
SMPTE (30°)
Comfort viewing distance; the entire screen is visible with eyes fixed at the centre. Suitable for larger rooms or multiple viewers.
Popular TV Sizes – Quick Reference
| Size | W × H (cm) | THX distance | Min. dist (4K) |
|---|---|---|---|
| 43" | 95 × 54 cm | ~1.1 m | ~0.5 m |
| 55" | 122 × 68 cm | ~1.4 m | ~0.7 m |
| 65" | 144 × 81 cm | ~1.7 m | ~0.8 m |
| 75" | 166 × 93 cm | ~1.9 m | ~0.9 m |
| 85" | 188 × 106 cm | ~2.2 m | ~1.1 m |