Energy Converter

A small calorie (cal) is the energy to raise 1g of water by 1°C. A food Calorie (Cal / kcal) = 1,000 small calories. When nutrition labels say 200 calories, they mean 200 kcal = 836,800 joules.

1 kilowatt-hour (kWh) = 3,600,000 joules (3.6 MJ). This is the unit electricity companies charge per. The average US household uses about 900 kWh per month.

A BTU (British Thermal Unit) is the energy needed to raise 1 pound of water by 1°F. 1 BTU = 1,055.06 joules. Used for rating air conditioners, heaters, and furnaces in the US.

The joule (J) is the SI unit of energy. 1 joule = 1 watt × 1 second = 1 newton × 1 metre. One joule is roughly the energy needed to lift a small apple (100g) by 1 metre.

1 kWh = 3,600,000 J = 860,420 small calories ≈ 860 kcal (food Calories). Running a mile burns roughly 80–100 kcal, equivalent to about 0.1 kWh of energy.