Kilocalorie to calorie online energy conversion formula, example

1 kilocalorie (kcal) = 1000 calories (cal)

1 calorie (cal) = 0.001 kilocalories (kcal)

Kilocalorie (kcal)

Definition: A kilocalorie (symbol: kcal or Cal) is a unit of energy equal to 1,000 small calories or 4.1868 kilojoules. In food science, when you see Calories (with a capital C) on labels, it actually refers to kilocalories.

Origin: The term was first used in 1824 by Nicolas Clément, derived from the Latin word calor (meaning heat). Later, in 1887, Wilbur Olin Atwater introduced the kilocalorie in the U.S. for measuring food energy and body activity.

Current Use: Though technically obsolete after SI units were adopted, kilocalories are still widely used on food labels around the world, often alongside kilojoules.

Calorie (cal)

Definition: One small calorie (cal) is the energy required to raise the temperature of 1 gram of water by 1°C.

Relation to Kilocalorie: 1 kilocalorie (kcal) = 1,000 calories (cal). In food labeling, Calories (capital C) usually mean kilocalories.

Origin: Introduced in 1824 by Nicolas Clément and popularized in the U.S. in 1887 by Atwater.

Current Use: The small calorie is largely outdated, but the kilocalorie (food calorie) is still widely used to measure energy in food and nutrition.

Conversion Formula

1 kilocalorie (kcal) = 1000 calories (cal)

1 calorie (cal) = 0.001 kilocalories (kcal)

Example: Convert 15 kcal to calories: 15 × 1000 = 15,000 calories (cal)

Quick Reference Conversions

• 0.01 kcal = 10 cal

• 0.1 kcal = 100 cal

• 1 kcal = 1000 cal

• 2 kcal = 2000 cal

• 5 kcal = 5000 cal

• 10 kcal = 10,000 cal

• 50 kcal = 50,000 cal

• 100 kcal = 100,000 cal

• 1000 kcal = 1,000,000 cal