Home Theater Room Size Calculator
A 20 x 14 x 9 ft room fits two rows, a 103–125" screen, a 7.5" riser, and 7.1.4. Enter your finished dimensions for your own estimate, then open the linked calculators to fine-tune each part.
How the estimate works
- Screen: 16:9, bottom 24" off the floor, 6" below the ceiling, 18" each side for L/R speakers. Range is SMPTE 30° to THX 36° from row 1.
- Rows: 52" apart, 1.5 ft behind the last row, row 1 at least 6 ft back. Each row needs 25°+ of screen (SMPTE ST 196M) and 7 ft of headroom over its riser (IRC minimum ceiling).
- Seats: 36" recliners, no aisle.
- Speakers: our rules of thumb. 7.1 needs 15 ft x 11 ft. Heights need 7.5 ft; two pairs need 8 ft and 15 ft of length.
- Limits: rectangular room, flat screen on the short wall. Doors, soffits, and acoustically transparent screens change the answer.
