15 kJ to cal — 15 kilojoules in calories
Exact 15 × 239.005736 = 3,585.09
15 kilojoules in other units
| Joules | 15,000 | J |
|---|---|---|
| Megajoules | 0.015 | MJ |
| Watt-hours | 4.166667 | Wh |
| Kilowatt-hours | 0.004166666667 | kWh |
| Calories | 3,585.09 | cal |
| Kilocalories | 3.585086 | kcal |
| British thermal units | 14.217257 | BTU |
| Therms | 0.000142172568 | thm |
| Foot-pounds | 11,063.43 | ft·lbf |
| Electronvolts | 93,622,636,116,911,438,430,208 | eV |
kJ to cal at a glance
| Kilojoules | Calories |
|---|---|
| 1 kJ | 239.005736 cal |
| 2 kJ | 478.011472 cal |
| 3 kJ | 717.017208 cal |
| 5 kJ | 1,195.03 cal |
| 10 kJ | 2,390.06 cal |
| 20 kJ | 4,780.11 cal |
| 25 kJ | 5,975.14 cal |
| 50 kJ | 11,950.29 cal |
| 100 kJ | 23,900.57 cal |
| 250 kJ | 59,751.43 cal |
| 500 kJ | 119,502.87 cal |
| 1,000 kJ | 239,005.74 cal |
How to convert kilojoules to calories
Multiply by 239.005736 — one kilojoule is 239.005736 calories. That factor is exact: it comes from the definition of the units rather than from a measurement, so it will not change and does not need rounding.
Working 15 × 239.005736 = 3,585.09
In words: about three thousand five hundred eighty-five calories.
What these units are
The kilojoule and the calorie are covered in the energy unit guide, along with every other unit on this page.
Questions
How many calories are in a kilojoule?
One kilojoule is 239.005736 calories. This figure is exact — it comes from the definition of the unit, not a measurement.
What is 15 kilojoules in calories?
15 kilojoules is 3,585.09 calories. The working is 15 × 239.005736 = 3,585.09.
Is a food Calorie the same as a calorie?
No — it is a thousand of them. The Calorie on a nutrition label is a kilocalorie, written with a capital C in principle and almost never in practice. A 250 Calorie chocolate bar holds 250,000 physics calories, or about 1,046 kilojoules, which is why European labels quote kJ alongside.
What does a kilowatt-hour actually represent?
One kilowatt drawn for one hour — a 1,000 W heater running for sixty minutes, or a 100 W bulb for ten hours. It is the unit your electricity bill is priced in, and it equals exactly 3.6 million joules.
How much energy is one BTU?
Roughly the heat needed to raise one pound of water by one degree Fahrenheit — about 1,055 joules, or the energy in a single kitchen match. Air conditioners are rated in BTU per hour, where a 12,000 BTU/h unit is one "ton" of cooling and draws around 3.5 kW of heat.
Why is the electronvolt so small?
Because it is sized for single particles: it is the energy one electron picks up crossing a one-volt potential difference. At about 1.6 × 10⁻¹⁹ joules it would be absurd for anything larger, which is precisely why particle physics uses it instead of dragging around twenty leading zeros.