Calorie to Gigajoule Converter

Energy · unit-converter

Convert Calorie 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: Calorie (cal)

To: Gigajoule (gj)

About Calorie

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

About Gigajoule

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

How to convert calories to gigajoules

1 calorie is equal to 4.18400000e-9 gigajoule when both are expressed in joule-equivalents:

1 cal = (4.184 J ÷ 1,000,000,000 J) gj = 4.18400000e-9 gj

Each calorie is defined as 4.184 J and each gigajoule as 1,000,000,000 J in this tool, so one cal equals 4.184 ÷ 1,000,000,000 gj = 4.18400000e-9 gj.

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

d(gj) = d(cal) × (4.184 / 1,000,000,000)

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

d(gj) = d(cal) ÷ 2.39005736e+8

Or: gigajoule = calorie ÷ 2.39005736e+8

Examples

Example #1: Convert 1 cal to gigajoule

1 cal = 1 cal × (4.184/1,000,000,000) gj = 0.0000000042 gj

1 cal = 1 cal ÷ 2.39005736e+8 = 0.0000000042 gj

Example #2: Convert 10 cal to gigajoule

10 cal = 10 cal × (4.184/1,000,000,000) gj = 0.0000000418 gj

10 cal = 10 cal ÷ 2.39005736e+8 = 0.0000000418 gj

Summary

To convert Calorie to Gigajoule, multiply the value in cal by the ratio of joules per cal divided by joules per gj. Equivalently: value_gj = value_cal × (4.184 / 1000000000). Numerically, 1 cal equals 4.1840000000000004e-9 gj.

Relationship context

You are converting between food / nutrition energy (calories) (Calories) and SI energy (joules) (Gigajoules). All values are mapped through joules first. The numeric factor is 4.184000e-9.

Conversion tables

Calorie (cal)Gigajoule (gj)
0.10.0000000004
10.0000000042
20.0000000084
30.0000000126
40.0000000167
50.0000000209
60.0000000251
70.0000000293
80.0000000335
90.0000000377
Calorie (cal)Gigajoule (gj)
100.0000000418
200.0000000837
300.0000001255
400.0000001674
500.0000002092
600.000000251
700.0000002929
800.0000003347
900.0000003766
1000.0000004184