Energy Converter (BTU, kWh, joules, calories)
Type in either box to convert BTU to kWh, kWh to BTU, kcal to kJ or any pair of energy units, with the answer in every unit at once.
Type in either box. Tap a unit under a box to change it.
Power is energy per second. Watts, BTU/h and AC tons times hours give energy.
BTU to kWh table
Common values both ways. Change the units above and the table follows.
| BTU | kWh |
|---|---|
| 1 | 0.0002930711 |
| 5 | 0.001465355 |
| 10 | 0.002930711 |
| 100 | 0.02930711 |
| 500 | 0.1465355 |
| 1,000 | 0.2930711 |
| 2,000 | 0.5861421 |
| 3,412 | 0.9999585 |
| 5,000 | 1.465355 |
| 8,000 | 2.344569 |
| 10,000 | 2.930711 |
| 12,000 | 3.516853 |
| 18,000 | 5.275279 |
| 24,000 | 7.033706 |
| 50,000 | 14.65355 |
| 100,000 | 29.30711 |
| kWh | BTU |
|---|---|
| 1 | 3,412.142 |
| 5 | 17,060.71 |
| 10 | 34,121.42 |
| 100 | 341,214.2 |
| 500 | 1,706,071 |
| 1,000 | 3,412,142 |
| 2,000 | 6,824,283 |
| 3,412 | 11,642,230 |
| 5,000 | 17,060,710 |
| 8,000 | 27,297,130 |
| 10,000 | 34,121,420 |
| 12,000 | 40,945,700 |
| 18,000 | 61,418,550 |
| 24,000 | 81,891,400 |
| 50,000 | 170,607,100 |
| 100,000 | 341,214,200 |
Common examples
- 1 unit of electricity1 kWh = 3,412 BTU = 3.6 MJ = 860 kcal
- Daily food intake (example)2,000 kcal = 8,368 kJ = 2.32 kWh
- A 100-Calorie snack100 kcal = 418.4 kJ
- Gas bill therm1 therm = 29.31 kWh = 105.5 MJ
- 12,000 BTU AC running 1 hour12,000 BTU = 3.52 kWh of heat moved
- Phone battery (typical)15 Wh = 54 kJ
- Natural gas trading unit1 MMBtu = 293.1 kWh = 10 therms
- Energy statistics1 toe = 11.63 MWh = 41.868 GJ
- One gigajoule1 GJ = 277.8 kWh
“Typical” and “example” figures are everyday illustrations, not measurements of your own devices or diet.
More converters: all units · pressure · data storage · speed · area · volume · °C to °F · lbs to kg · inches to cm · feet to metres · oz to grams · miles to km
How your energy is converted
Every unit goes into joules first, then out to the unit you want.
- 1
Your amount
10,000 BTU →
kWh - 2
Into joules
10,000 × 1,055.056 =
10,550,560 J - 3
Out to kWh
10,550,560 ÷ 3,600,000 =
2.930711 kWh - 4
The shortcut
1 BTU =
0.0002930711 kWh
Read more: the formula, a worked example, kWh to BTU, food Calories, therms and AC tons
The formula
joules = your number × joules in one of your unit
answer = joules ÷ joules in one of the unit you want
BTU → kWh: kWh = BTU ÷ 3,412.142
kWh → BTU: BTU = kWh × 3,412.142
Worked example
10,000 BTU in kWh. First into joules: 10,000 × 1,055.056 = 10,550,560 J (10,550,558.5 J before rounding). Then out to kWh, where 1 kWh is 3,600,000 J: 10,550,558.5 ÷ 3,600,000 = 2.930711 kWh. As a shortcut, 1 BTU = 0.0002930711 kWh.
The other way, kWh to BTU: 3 kWh × 3,412.142 = 10,236.4 BTU.
| 1 of this | In joules | Where it’s used |
|---|---|---|
| BTU | 1,055.05585262 | Heating, AC and gas in the US and UK |
| kWh | 3,600,000 (exact) | Electricity bills (“units”), batteries, EVs |
| Wh | 3,600 (exact) | Phone and laptop batteries |
| kcal (food Calorie) | 4,184 (exact) | Food labels, exercise |
| cal | 4.184 (exact) | Chemistry |
| kJ / MJ / GJ | 1,000 / 10⁶ / 10⁹ | Food labels in kJ, fuels, gas bills |
| therm | 105,505,585.262 | Gas bills (100,000 BTU) |
| TR·h | 12,660,670.23 | Cooling: 1 AC ton running for 1 hour |
| eV | 1.602176634 × 10⁻¹⁹ (exact) | Physics, atoms and light |
Energy or power?
Energy is an amount: kWh, BTU, joules, calories. Power is how fast energy is used: watts, BTU per hour, horsepower and “tons” of air conditioning. Energy = power × time. A 1.5 kW heater for 3 hours uses 1.5 × 3 = 4.5 kWh. An AC rated at 12,000 BTU/h (1 ton of refrigeration, 3.517 kW) moves 12,000 BTU of heat each hour. Its electricity use is lower, because AC units move more heat than the power they draw.
Food Calories
The Calorie on a food label is a kilocalorie. 1 kcal = 4.184 kJ, so a 2,000 kcal day is 8,368 kJ, or 2.32 kWh.
Which BTU and which therm?
This page uses the International Table BTU (1,055.05585262 J), the one most engineering tables use. A therm here is 100,000 of those BTU (the EU and UK therm). The US therm is defined slightly differently (about 0.02% smaller), which only matters for the last digits.
Factors are exact by definition: 1 cal = 4.184 J (thermochemical), 1 cal (IT) = 4.1868 J, 1 BTU = 1,055.05585262 J, 1 eV = 1.602176634 × 10⁻¹⁹ J (SI, 2019), 1 toe = 41.868 GJ (IEA convention). Checked 11 October 2026 against NIST Special Publication 811.
Common questions
How do I convert BTU to kWh?
Divide BTU by 3,412.14, or multiply by 0.000293071. So 10,000 BTU is 2.93 kWh. Behind the scenes, 1 BTU is 1,055.056 joules and 1 kWh is exactly 3,600,000 joules, so the converter goes through joules.
How do I convert kWh to BTU?
Multiply kWh by 3,412.14. One unit of electricity (1 kWh) is 3,412 BTU, and 3 kWh is 10,236 BTU. Use the swap button above to turn any BTU to kWh answer into kWh to BTU with the same amount.
Is a food Calorie the same as a calorie?
No. The Calorie on food labels (capital C) is a kilocalorie, 1,000 small calories. 1 kcal is 4.184 kJ, so a 2,000 kcal day is 8,368 kJ. Countries that label food in kilojoules use the same 4.184 figure.
What does 12,000 BTU mean on an air conditioner?
It means 12,000 BTU per hour, which is power, not an amount of energy. That is 1 ton of refrigeration, or 3.517 kW of cooling. Run it for one hour and it moves 12,000 BTU (3.517 kWh) of heat. Advanced has a power × time helper.
How many kWh is a therm?
A therm is 100,000 BTU, which is 29.31 kWh or 105.5 MJ. Gas bills in some countries are in therms and in others in kWh. Ten therms make one MMBtu, the unit used for natural gas prices.
How many joules is 1 kWh?
Exactly 3,600,000 joules (3.6 MJ). A kilowatt is 1,000 joules every second, and an hour has 3,600 seconds, so 1,000 × 3,600 = 3,600,000. A watt-hour is 3,600 joules.
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