BTU to kW converter
1 kW ≈ 3,412 BTU/hr. Convert either way below, or use the table of common air conditioning sizes.
1 kW ≈ 3,412 BTU/hr. Type in either box.
Common air conditioning sizes
| Unit size (kW) | BTU/hr |
|---|---|
| 2.0 kW | 6,824 |
| 2.5 kW | 8,530 |
| 3.5 kW | 11,942 |
| 5.0 kW | 17,060 |
| 6.0 kW | 20,472 |
| 7.1 kW | 24,225 |
| 8.0 kW | 27,296 |
| 10.0 kW | 34,120 |
Not sure what size you need? The air conditioning size calculator works it out from your room, or see size and cost by room.
Frequently asked questions
How many BTU is 1 kW?
1 kW is about 3,412 BTU per hour. To convert kW to BTU/hr, multiply by 3,412; to convert BTU/hr to kW, divide by 3,412.
How many kW is 12,000 BTU?
12,000 BTU/hr is about 3.5 kW. In the UK that's usually sold as a 3.5 kW unit, which suits a typical room of roughly 23–35 m² using the 0.10–0.15 kW per m² rule of thumb.
How many kW is 9,000 BTU?
9,000 BTU/hr is about 2.6 kW — usually sold as a 2.5 kW unit, which suits a typical room of roughly 17–25 m² — a common size for bedrooms.
Why do UK air conditioners use kW instead of BTU?
UK and European manufacturers rate capacity in kilowatts; BTU is the older imperial unit still common in the US and on some portable units. They measure the same thing — the rate a unit moves heat.