Convert calories to kilocalories

Explanation

From this page you can convert calories to kilocalories (or cal to kcal) simply, by using the application above.

In case you are wondering, to convert from calories to kilocalories you need to multiply by 0.001. This factor is calculated using the respective definitions of the two units you can find below.

Formula

1 cal=0.001 kcal

caloriescal

dimension	energy
symbol	cal

The calorie (cal) is a unit of energy.

In this converter "calorie" refers to the thermochemical calorie.

When talking about food the word calorie almost always refers to the kilocalorie (kcal).

Definition of the calorie

One calorie is 4.184 joules.

NIST Guide to the SI, Appendix B.9

History

The calorie was first defined as the amount of energy needed to raise the temperature of one kilogram of water by one degree Celsius.

The "Thermochemical calorie" was defined by Frederick Rossini simply as 4.1833 international joules in order to avoid the difficulties associated with uncertainties about the heat capacity of water. ^[source]

In 1948 the CGPM abandonned the international ampere for the absolute ampere, ^[source] as a result, the thermochemical calorie was redefined as 4.184 joules exactly to represent the same quantity of energy as before.

Some Facts

Since the tonne of TNT is defined as 4.184 gigajoules, one calorie is the energy equivalent to the detonation of one milligram of TNT (or one nanotonne of TNT).

Calories

calorie	cal	1
kilocalorie	kcal	1000

Related Conversions

kilocalorieskcal

dimension	energy
symbol	kcal

The kilocalorie (kcal) is a unit of energy.

Note: when talking about food the word calorie almost always refers to the kilocalorie (kcal). Since there is a factor 1000 between the calorie and the kilocalorie, you probably should double-check.

Definition of the kilocalorie

One kilocalorie is 1000 calories.

Equivalences

One kilocalorie is equivalent to:

Calories

calorie	cal	1
kilocalorie	kcal	1000