Calorie to Kilocalorie Converter

Energy · unit-converter

Convert Calorie to Kilocalorie with fixed input and output units, a step-by-step formula line, and reference tables. Factors are joule-based; food energy uses thermochemical calories. The full Energy Converter also includes MMBtu, toe, thermal kWh, and MeV/GeV.

Calculator

From: Calorie (cal)

To: Kilocalorie (kcal)

About Calorie

The small calorie (cal) is 4.184 J in this converter (thermochemical). Do not confuse with the dietary kilocalorie (kcal).

About Kilocalorie

The kilocalorie (kcal) is 1,000 calories in the nutrition sense—often labeled “Calorie” on food packaging. Here 1 kcal = 4,184 J (thermochemical calorie definition used in this tool).

How to convert calories to kilocalories

1 calorie is equal to 0.001 kilocalorie when both are expressed in joule-equivalents:

1 cal = (4.184 J ÷ 4,184 J) kcal = 0.001 kcal

Each calorie is defined as 4.184 J and each kilocalorie as 4,184 J in this tool, so one cal equals 4.184 ÷ 4,184 kcal = 0.001 kcal.

Let d(cal) be the numeric amount in Calorie (cal), and d(kcal) the amount in Kilocalorie (kcal). Then:

d(kcal) = d(cal) × (4.184 / 4,184)

Equivalently, divide by how many cal fit into one kcal (joules per kcal divided by joules per cal):

d(kcal) = d(cal) ÷ 1000

Or: kilocalorie = calorie ÷ 1000

Examples

Example #1: Convert 1 cal to kilocalorie

1 cal = 1 cal × (4.184/4,184) kcal = 0.001 kcal

1 cal = 1 cal ÷ 1000 = 0.001 kcal

Example #2: Convert 10 cal to kilocalorie

10 cal = 10 cal × (4.184/4,184) kcal = 0.01 kcal

10 cal = 10 cal ÷ 1000 = 0.01 kcal

Summary

To convert Calorie to Kilocalorie, multiply the value in cal by the ratio of joules per cal divided by joules per kcal. Equivalently: value_kcal = value_cal × (4.184 / 4184). Numerically, 1 cal equals 0.001 kcal.

Relationship context

Both units are food / nutrition energy (calories). Conversions use fixed joule factors, so results stay consistent with the definitions in this converter. The factor from Calorie to Kilocalorie is 1.000000e-3 (1 cal = 0.001 kcal).

Conversion tables

Calorie (cal)Kilocalorie (kcal)
0.10.0001
10.001
20.002
30.003
40.004
50.005
60.006
70.007
80.008
90.009
Calorie (cal)Kilocalorie (kcal)
100.01
200.02
300.03
400.04
500.05
600.06
700.07
800.08
900.09
1000.1