Uses the same engine as the full calculator (occupants 2, one large window assumed).
| Cooling load | — |
Common 900 sq ft dimensions: 30×30 ft, 25×36 ft, 20×45 ft. If you searched for one of these room sizes, this is your page — the load math depends on area, not shape.
US (whole home, central system): at the moderate-climate rate of ~22 BTU per sq ft, 900 sq ft works out to 19,800 BTU/hr, i.e. a 2 ton unit. Your climate zone shifts this substantially:
| US climate zone | Cooling load | Central AC size |
|---|---|---|
| Zone 1 — Hot (FL, S.TX, AZ desert) | 25,200 BTU/hr | 2.5 ton |
| Zone 2 — Warm (Deep South, TX) | 22,500 BTU/hr | 2 ton |
| Zone 3 — Moderate (TN, NC, MO) | 19,800 BTU/hr | 2 ton |
| Zone 4 — Mild (Mid-Atlantic, PNW) | 18,000 BTU/hr | 1.5 ton |
| Zone 5 — Cool (Upper Midwest, New England) | 16,200 BTU/hr | 1.5 ton |
India: 900 sq ft spans several rooms — Indian homes cool room-by-room with one split unit each. Use the whole-house calculator to plan units per room instead of one big system.
These figures assume 8 ft ceilings (9.5 ft for India), average insulation and normal sun. Your real number can swing ±30% — run the full tonnage calculator with your actual room data, including ceiling height, sun exposure and occupancy.
| Area | US central AC | India (single room) |
|---|---|---|
| 700 sq ft | 1.5 ton | multiple units |
| 800 sq ft | 1.5 ton | multiple units |
| 900 sq ft | 2 ton | multiple units |
| 1,000 sq ft | 2 ton | multiple units |
| 1,100 sq ft | 2.5 ton | multiple units |
0.75 ton 1 ton 1.5 ton 2 ton 2.5 ton 3 ton 3.5 ton 4 ton 5 ton
About 19,800 BTU/hr for a 900 sq ft US home in a moderate climate (22 BTU/sq ft), rising to 25,200 BTU/hr in hot Zone 1 climates like Florida or Arizona.
In a moderate US climate with average insulation, a 900 sq ft home carries roughly 19,800 BTU/hr of cooling load, which calls for a 2 ton system. Hot climates (Zone 1–2) push the load 15–25% higher; cool climates pull it lower.
900 sq ft is larger than a single Indian room — size each room separately with the whole-house calculator and fit one split unit per room.
100 sq ft 120 sq ft 150 sq ft 180 sq ft 200 sq ft 250 sq ft 300 sq ft 350 sq ft 400 sq ft 450 sq ft 500 sq ft 600 sq ft 700 sq ft 800 sq ft 1,000 sq ft 1,100 sq ft 1,200 sq ft 1,300 sq ft 1,400 sq ft 1,500 sq ft 1,600 sq ft 1,800 sq ft 2,000 sq ft 2,200 sq ft 2,400 sq ft 2,500 sq ft 2,800 sq ft 3,000 sq ft 3,200 sq ft 3,500 sq ft 4,000 sq ft 4,500 sq ft 5,000 sq ft
How these figures are derived: BTU per square foot, honestly · refine for your exact room with the full tonnage calculator.