The ultimate unit conversion tool for work and heat. Convert accurately between Joules (SI), Kilowatt-hours (Electricity), Calories (Food), and BTUs (Heating).
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In nutrition, when we say "Calories" (with a capital C), we actually mean **Kilocalories (kcal)**. This is 1,000 times larger than the small calorie (cal) used in chemistry.
Equal to 1 kcal (1000 small calories). This is what you see on food labels. Equal to 4,184 Joules.
The energy needed to heat 1 gram of water by 1°C. Equal to 4.184 Joules.
The standard SI unit. Food packaging in Europe and Australia lists energy in kJ (Kilojoules).
| Conversion | Multiplier | Reverse |
|---|---|---|
| kcal to Joules | × 4,184 | ÷ 4,184 |
| kWh to Joules | × 3,600,000 | ÷ 3,600,000 |
| BTU to Joules | × 1,055.06 | ÷ 1,055.06 |
| Foot-pound to Joules | × 1.3558 | ÷ 1.3558 |
You are billed in kWh. 1 kWh is the energy used by a 1,000 Watt appliance running for 1 hour. It equals 3.6 Megajoules.
Electric Vehicle battery capacity is measured in kWh. A typical EV has a 60-100 kWh battery.
Don't confuse kW (Power, rate of flow) with kWh (Energy, total amount). kW is like speed; kWh is like distance.