Energy

Divide Joules by 4.184. Example: 1000 J = 1000 ÷ 4.184 = 239 calories. Or multiply by 0.239. Note: 1 kilocalorie (kcal) = 1000 calories = 4184 Joules. Food "Calories" are actually kilocalories.

1 kilocalorie (kcal) = 1000 calories (cal). In nutrition, "Calorie" (capital C) = 1 kilocalorie = 1000 calories. Food labels show kilocalories but call them "Calories". Example: A 100 Calorie snack = 100 kcal = 100,000 calories = 418,400 Joules.

Multiply kWh by 3,600,000. Example: 1 kWh = 3,600,000 J = 3.6 MJ. kWh (kilowatt-hour) is commonly used for electricity billing. 1 kWh = 1000 watts × 3600 seconds = 3,600,000 Joules.