Kilocalorie to Gigajoule Converter

Energy · unit-converter

Convert Kilocalorie to Gigajoule 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: Kilocalorie (kcal)

To: Gigajoule (gj)

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).

About Gigajoule

One gigajoule is 1,000,000,000 J. Utility-scale and fuel-system reporting commonly use GJ.

How to convert kilocalories to gigajoules

1 kilocalorie is equal to 0.000004184 gigajoule when both are expressed in joule-equivalents:

1 kcal = (4,184 J ÷ 1,000,000,000 J) gj = 0.000004184 gj

Each kilocalorie is defined as 4,184 J and each gigajoule as 1,000,000,000 J in this tool, so one kcal equals 4,184 ÷ 1,000,000,000 gj = 0.000004184 gj.

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

d(gj) = d(kcal) × (4,184 / 1,000,000,000)

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

d(gj) = d(kcal) ÷ 239005.7361376672925

Or: gigajoule = kilocalorie ÷ 239005.7361376672925

Examples

Example #1: Convert 1 kcal to gigajoule

1 kcal = 1 kcal × (4,184/1,000,000,000) gj = 0.000004184 gj

1 kcal = 1 kcal ÷ 239005.7361376672925 = 0.000004184 gj

Example #2: Convert 10 kcal to gigajoule

10 kcal = 10 kcal × (4,184/1,000,000,000) gj = 0.00004184 gj

10 kcal = 10 kcal ÷ 239005.7361376672925 = 0.00004184 gj

Summary

To convert Kilocalorie to Gigajoule, multiply the value in kcal by the ratio of joules per kcal divided by joules per gj. Equivalently: value_gj = value_kcal × (4184 / 1000000000). Numerically, 1 kcal equals 0.000004184 gj.

Relationship context

You are converting between food / nutrition energy (calories) (Kilocalories) and SI energy (joules) (Gigajoules). All values are mapped through joules first. The numeric factor is 4.184000e-6.

Conversion tables

Kilocalorie (kcal)Gigajoule (gj)
0.10.0000004184
10.000004184
20.000008368
30.000012552
40.000016736
50.00002092
60.000025104
70.000029288
80.000033472
90.000037656
Kilocalorie (kcal)Gigajoule (gj)
100.00004184
200.00008368
300.00012552
400.00016736
500.0002092
600.00025104
700.00029288
800.00033472
900.00037656
1000.0004184