Convert Calories to Kilowatt-hours
1 calorie is 0.000001 kWh. One calorie is exactly 0.00000116222222222 kilowatt-hours.
One calorie is 1.1622 × 10^-6 kilowatt-hours. To convert calories to kilowatt-hours, multiply by 1.1622 × 10^-6; to go the other way, divide by 1.1622 × 10^-6 or multiply by 860420.65. The factor is exact rather than rounded: it follows from NIST Special Publication 811. The thermochemical calorie: exactly 4.184 joules by definition.
Factor checked against the defining standard · How we check
- Calories × 1.1622 × 10^-6
value * 0.000001162222222220 kWh
1 calorie in every energy unit
| Unit | Value | Exact factor |
|---|---|---|
| joules | 4.184 J | × 4.184 |
| kilojoules | 0.004184 kJ | × 0.004184 |
| calories (as entered) | 1 cal | — |
| kilocalories | 0.001 kcal | × 0.001 |
| watt-hours | 0.001162222222 Wh | × 0.00116222222222 |
| kilowatt-hours | 0.000001162222222 kWh | × 0.00000116222222222 |
| British thermal units | 0.003965666831 BTU | × 0.00396566683139 |
| foot-pounds | 3.085960033 ft·lbf | × 3.08596003258 |
Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert calories to kilowatt-hours?
- 1.Take the measurement in calories.
- 2.Multiply by 1.1622 × 10^-6 — that is how many kilowatt-hours fit in one calorie.
- 3.To go back the other way, divide by 1.1622 × 10^-6, or multiply by 860420.65.
Worked example: 25 calories to kilowatt-hours
- Formula
- cal × 1.1622 × 10^-6 = kWh
- Arithmetic
- 25 × 1.1622 × 10^-6 = 0.000029 kWh
- Answer
- 25 cal = 0.000029 kWh
The factor is rounded for display; the figure above is computed from the full value.
Calories to kilowatt-hours conversion table
| Calories | Kilowatt-hours |
|---|---|
| 1 cal | 0.000001 kWh |
| 2 cal | 0.000002 kWh |
| 3 cal | 0.000003 kWh |
| 4 cal | 0.000005 kWh |
| 5 cal | 0.000006 kWh |
| 6 cal | 0.000007 kWh |
| 7 cal | 0.000008 kWh |
| 8 cal | 0.000009 kWh |
| 9 cal | 0.00001 kWh |
| 10 cal | 0.000012 kWh |
| 12 cal | 0.000014 kWh |
| 15 cal | 0.000017 kWh |
| 20 cal | 0.000023 kWh |
| 25 cal | 0.000029 kWh |
| 50 cal | 0.000058 kWh |
| 100 cal | 0.000116 kWh |
| 200 cal | 0.000232 kWh |
| 300 cal | 0.000349 kWh |
| 500 cal | 0.000581 kWh |
| 1000 cal | 0.001162 kWh |
| 2000 cal | 0.002324 kWh |
| 5000 cal | 0.005811 kWh |
| 10000 cal | 0.011622 kWh |
What is a calorie?
The thermochemical calorie: exactly 4.184 joules by definition. This is the small calorie — the one on a food label is a thousand of these, which is the single most common confusion in this group.
What is a kilowatt-hour?
A thousand watt-hours, and the unit every electricity bill is added up in. Exactly 3.6 megajoules, and the reason a 100 W bulb left on for ten hours costs one unit.
How many kilowatt-hours are in a calorie?
One calorie is 1.1622 × 10^-6 kilowatt-hours. Going the other way, one kilowatt-hour is 860420.65 calories. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every energy unit here
| Unit | Symbol | One of these is |
|---|---|---|
| Joules | J | the base unit |
| Kilojoules | kJ | 1000 joule |
| Calories | cal | 4.184 joule |
| Kilocalories | kcal | 4184 joule |
| Watt-hours | Wh | 3600 joule |
| Kilowatt-hours | kWh | 3600000 joule |
| British thermal units | BTU | 1055.0559 joule |
| Foot-pounds | ft·lbf | 1.3558179 joule |
Source: NIST Special Publication 811 — the thermochemical calorie is exactly 4.184 J
Questions people actually ask
- How many kilowatt-hours are in a calorie?
- 1.1622 × 10^-6. A thousand watt-hours, and the unit every electricity bill is added up in. Exactly 3.6 megajoules, and the reason a 100 W bulb left on for ten hours costs one unit.
- How do I convert kilowatt-hours back to calories?
- Divide by 1.1622 × 10^-6, or multiply by 860420.65 — they are the same operation.
Other energy conversions
Kilowatt-hours to calories — the same conversion the other way.