Plug Count

12,000 BTU air conditioner: room size, watts and cost

A 12,000 BTU air conditioner cools about 450 up to 550 sq ft, per ENERGY STAR's sizing chart (8-foot ceilings). It draws roughly 816–1,101 W, about 6.8–9.2 amps at 120 V.

Room size
450–550 sq ftENERGY STAR chart
Power
816–1,101 WEfficient to older
Per hour
13¢–18¢At 16.48¢/kWh

Check your room

ENERGY STAR's method: size by floor area, then adjust for sun, people and kitchens.

Recommended size
12,000 BTUENERGY STAR chart for 450 sq ft
Nearest common unit
12,000 BTUWindow or portable AC
Approx. power
816–1,101 WEfficient to older models

Power, amps and cost

Efficient (ENERGY STAR)Older (2014 minimum)
Watts816 W1,101 W
Amps at 120 V6.8 A9.2 A
Cost per hour13¢18¢

Watts ≈ BTU ÷ CEER (combined energy efficiency ratio). CEER includes standby power, so running watts are approximate; check the unit's label.

Sizing chart

ENERGY STAR room air conditioner sizing
Area to coolCapacity needed
100 to 150 sq ft5,000 BTU/hr
150 to 250 sq ft6,000 BTU/hr
250 to 300 sq ft7,000 BTU/hr
300 to 350 sq ft8,000 BTU/hr
350 to 400 sq ft9,000 BTU/hr
400 to 450 sq ft10,000 BTU/hr
450 to 550 sq ft12,000 BTU/hr
550 to 700 sq ft14,000 BTU/hr
700 to 1,000 sq ft18,000 BTU/hr
1,000 to 1,200 sq ft21,000 BTU/hr
1,200 to 1,400 sq ft23,000 BTU/hr
1,400 to 1,500 sq ft24,000 BTU/hr
1,500 to 2,000 sq ft30,000 BTU/hr
2,000 to 2,500 sq ft34,000 BTU/hr

ENERGY STAR chart, assuming 8-foot ceilings. Heavily shaded: −10%. Very sunny: +10%. More than two people: +600 BTU each. Kitchen: +4,000 BTU.

Questions people ask

How many square feet does a 12,000 BTU air conditioner cool?

A 12,000 BTU air conditioner cools about 450 up to 550 sq ft , per ENERGY STAR's sizing chart (8-foot ceilings).

How many watts does a 12,000 BTU air conditioner use?

About 816 W for an efficient model to 1,101 W for an older one (BTU ÷ CEER).

How much does it cost to run a 12,000 BTU air conditioner?

About 13¢–18¢ per hour of compressor run time at the US average 16.48¢/kWh; 8 hours a day for a month is roughly $32.72–$44.12.

Does a 12,000 BTU air conditioner need a 240 V outlet?

Check the nameplate. Many large window units run on 120 V, but some of the largest need a 240 V outlet or a dedicated circuit. Use the plug type and circuit the manufacturer specifies.

Sources