BTU to kW Converter
Convert BTU per hour to kilowatts and back — the HVAC sizing conversion, with the rate-vs-energy distinction made plain.
Convert BTU/h ⇄ kW
Formula: 12000 BTU/h (BTU/h ÷ 3,412.14) = 3.5169 kW
How the btu to kw conversion works
The conversion is exact: kilowatts = BTU per hour ÷ 3,412.14. One watt equals 3.41214 BTU per hour, so one kilowatt (1,000 watts) equals 3,412.14 BTU/h. Going the other way, BTU/h = kW × 3,412.14.
Rate, not total energy: this page converts a rate — BTU per hour, the figure on air-conditioner and heater nameplates — into kilowatts, also a rate. A bare BTU figure with no time attached is an amount of energy, not a power rating; that conversion is BTU to kWh. If your unit says just “BTU” on a cooling spec, it almost always means BTU/h.
Worked example: a 12,000 BTU/h air conditioner — the classic “1-ton” unit — is 12,000 ÷ 3,412.14 = 3.52 kW of cooling. And a 5 kW heater outputs 5 × 3,412.14 = 17,061 BTU/h. For the reverse energy question, see watts to BTU per hour and BTU to kWh.
Handy benchmarks: 5,000 BTU/h = 1.47 kW, 9,000 BTU/h = 2.64 kW, 12,000 BTU/h = 3.52 kW, 18,000 BTU/h = 5.27 kW and 24,000 BTU/h = 7.03 kW.
btu to kw converter questions
How many BTU per hour are in 1 kW?
How do I convert BTU to kW?
What is 12,000 BTU in kW?
Is BTU the same as BTU/h?
How do I convert kW back to BTU?
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Sources & official guidance
Exact power conversion — 1 kW = 3,412.14 BTU/h. BTU figures on appliance specs mean BTU/h unless stated otherwise. See our disclaimer.