What size air conditioner for 700 sq ft? BTU answer and adjustments
For 700 square feet, the baseline is 14,000 BTU/h (20 BTU per sq ft) — about 1.17 tons or 4.1 kW of cooling. Adjust to 15,400 BTU for a sun-baked room, 12,600 for a shaded one, 18,000 if it is a kitchen, and add 600 BTU per regular occupant beyond two.
| Scenario | Rule | BTU/h |
|---|---|---|
| Baseline room | 700 × 20 | 14,000 |
| Very sunny | +10% | 15,400 |
| Heavily shaded | −10% | 12,600 |
| Kitchen | +4,000 | 18,000 |
| Four regular occupants | +600 × 2 | 15,200 |
Conversions: 12,000 BTU/h = 1 ton = 3.517 kW. 14,000 BTU/h ≈ 1.17 tons ≈ 4.1 kW. Figures are cooling capacity to look for on the spec sheet, not electrical input.
From BTU to a product
Translated to the shelf, 700 sq ft means a 12,000–14,000 BTU window unit or a 12k mini-split head. Take the next size up from your adjusted figure and stop there; inverter units absorb a 10–20% margin gracefully, a doubling never.
Related: BTU sizing explained, window vs portable, and for whole-house equipment the central AC guide. Metric version: puissance par m² (French).
Frequently asked questions
How many BTU for 700 square feet?
14,000 BTU/h as a baseline (20 BTU/sq ft), 15,400 for a very sunny room, 12,600 for a shaded one, plus 4,000 for a kitchen and 600 per occupant beyond two. That is about 1.17 tons or 4.1 kW.
What size AC unit is that?
A 12,000–14,000 BTU window unit or a 12k mini-split head. For whole-house systems serving several enclosed rooms, a Manual J load calculation replaces this room-level rule.
Is 20 BTU per square foot always right?
It is the room-unit baseline ENERGY STAR and the DOE use; ceiling height above 8 ft, poor insulation and big west glazing push it higher, while a well-insulated shaded room can sit lower. The adjustments above capture the common cases.