Convert Kilowatt-Hours to BTU
Kilowatt-hours to BTU is the conversion you need when the unit on your electricity bill has to meet the world of heating and cooling, where energy is quoted in British Thermal Units. A kilowatt-hour is what you use when 1000 watts run for one hour, and one kilowatt-hour is approximately 3412.14 BTU — the classic figure behind every electric-heat calculation.
Kilowatt-hours to British thermal units conversion table
| Kilowatt-hours (kWh) | British thermal units (BTU) |
|---|---|
| 1 | 3,412.141633 |
| 2 | 6,824.283266 |
| 3 | 10,236.424899 |
| 5 | 17,060.708166 |
| 10 | 34,121.416331 |
| 20 | 68,242.832663 |
| 50 | 170,607.081656 |
| 100 | 341,214.163313 |
| 500 | 1,706,070.816564 |
| 1,000 | 3,412,141.633128 |
The formula
To convert kilowatt-hours to BTU, multiply the number of kilowatt-hours by 3412.14:
BTU = kilowatt-hours × 3412.14
A worked example
Say you want to know what one kilowatt-hour is in BTU:
1 × 3412.14 = 3412.14 BTU
So one kilowatt-hour is about 3412 BTU — the standard "1 kWh ≈ 3412 BTU" heating figure you'll see all over HVAC math.
Why it's an approximation
The factor 3412.141633127942 is a rounded value. This uses the International Table BTU, which is defined from the calorie, and the calorie doesn't divide evenly into the kilowatt-hour's 3,600,000 joules. Dividing one by the other leaves a long, non-terminating decimal, so the result stays approximate no matter how many places you keep.
When you'll use it
Sizing electric heating against gas or a heat pump, reading the BTU rating on a heater or air conditioner next to what it costs to run, or turning your electricity usage into the BTU figures the heating-and-cooling trade works in.
Frequently asked questions
How many BTU are in a kilowatt-hour?
About 3412.14 BTU. It's a rounded figure — the exact value runs to many decimal places (3412.141633127942), so 3412.14 is the practical number, and you'll often see it shortened to '1 kWh ≈ 3412 BTU'.
Why does '3412 BTU per kWh' show up in HVAC math?
Because it converts electric energy into heat energy. An electric heater that draws one kilowatt-hour puts out about 3412 BTU of heat, so this figure is how installers size electric heating and compare it against gas or a heat pump.
Is the kilowatt-hours to BTU conversion exact?
No. This uses the International Table BTU, which is defined from the calorie and doesn't divide evenly into the kilowatt-hour, so the factor 3412.14 is rounded for everyday use. More decimal places give you more precision if you need it.