Energy Converter
Convert between joules, kWh, BTU, calories & more
Frequently Asked Questions
1 kWh = 3,600,000 joules (3.6 megajoules). A kWh is the standard unit electric utilities bill in.
1 calorie (small calorie, cal) = 4.184 joules. Food "Calories" (capital C) are actually kilocalories, so 1 food Calorie = 4,184 joules.
1 British Thermal Unit (BTU) = 1,055.06 joules. BTU is commonly used for rating HVAC equipment and furnaces in the US.
A calorie (lowercase, cal) is the energy to heat 1 gram of water by 1°C. A Calorie (uppercase, kcal) — used on food labels — is 1,000 times larger.