What Size AC for 700 Sq Ft?

A 700 sq ft space needs about 14,000 BTU/h of cooling (1.17 tons), so the nearest size is 14,000 BTU. This assumes an 8 ft ceiling and average sun. It is a rule of thumb (20 BTU per sq ft), not an engineered load.

Cooling needed13,998 BTU/h
Suggested AC size14,000 BTU
Cooling in tons1.17
Heating estimate27,996 BTU/h
Room area700 sq ft

AC size for 700 sq ft by situation

ScenarioBTU/hTonsSuggested size
Heavily shaded (−10%)12,6001.0514,000 BTU
Average sun, 8 ft ceiling14,0001.1714,000 BTU
Very sunny (+10%)15,4001.2818,000 BTU
Kitchen (+4,000 BTU)18,0001.518,000 BTU
9 ft ceilings (+12.5%)15,7501.3118,000 BTU
10 ft ceilings (+25%)17,5001.4618,000 BTU
Hot climate (+10%)15,4001.2818,000 BTU

Rule-of-thumb figures for a two-person space; each extra person over 2 adds about 600 BTU.

How it is calculated

700 sq ft × 20 BTU × (8 ÷ 8) = 14,000 BTU/h
14,000 ÷ 12,000 = 1.17 tons
Sunny: 14,000 × 1.1 = 15,400 · Kitchen: 14,000 + 4,000 = 18,000

Which type of AC for 700 sq ft?

  • Window unit – The usual choice at this size is a 14,000 BTU window unit. Units above roughly 15,000 BTU often need a 230V circuit, but this size normally stays on 115V.
  • Portable unit – Portable units lose capacity to exhaust-hose heat. Expect to need about 18,200 BTU nominal (≈30% more) to match a window unit here.
  • Mini-split – A 14,000 BTU single-zone mini-split is the quiet, efficient alternative and also heats, with no window blocked.

Frequently asked questions

How many BTU do I need for 700 square feet?

About 14,000 BTU/h for an 8 ft ceiling in average conditions (700 × 20). That is 1.17 tons, so the closest unit is 14,000 BTU.

Is 14,000 BTU enough for 700 sq ft if the room is sunny?

A very sunny space needs about 15,400 BTU, so 18,000 BTU is recommended – a step different from the 14,000 BTU for average sun.

What if the 700 sq ft space has 10 ft ceilings?

The load rises 25% to 17,500 BTU, so choose 18,000 BTU instead of 14,000 BTU. Volume matters, not just floor area.