Calories to Gigajoules Conversion

Enter the energy in calories below to get the value converted to gigajoules.

Results in Gigajoules:
Loading content.
1 cal = 4.184E-9 GJ
Hint: use a scientific notation calculator to convert E notation to decimal

How to Convert Calories to Gigajoules

To convert a calorie measurement to a gigajoule measurement, multiply the energy by the conversion ratio.

Since one calorie is equal to 4.184E-9 gigajoules, you can use this simple formula to convert:

gigajoules = calories × 4.184E-9

The energy in gigajoules is equal to the calories multiplied by 4.184E-9.

For example, here's how to convert 500,000,000 calories to gigajoules using the formula above.
500,000,000 cal = (500,000,000 × 4.184E-9) = 2.092 GJ

Calories and gigajoules are both units used to measure energy. Keep reading to learn more about each unit of measure.


One calorie is equal to the heat needed to raise the temperature of one gram of water from 14.5 to 15.5 degrees Celsius.

When measuring the energy content in foods, the large calorie, or kilocalorie is used, but it's often still just called a "calorie." When both the calorie and large calorie are used in the same context it is common to refer to the calorie as a "small calorie."

Calories can be abbreviated as cal; for example, 1 calorie can be written as 1 cal.


One gigajoule is equal to 1,000,000,000 joules, which are the energy equal to the force on an object of one newton at a distance of one meter.

The gigajoule is a multiple of the joule, which is the SI derived unit for energy. In the metric system, "giga" is the prefix for 109. Gigajoules can be abbreviated as GJ; for example, 1 gigajoule can be written as 1 GJ.

Calorie to Gigajoule Conversion Table

Calorie measurements converted to gigajoules
Calories Gigajoules
1 cal 0.000000004184 GJ
2 cal 0.000000008368 GJ
3 cal 0.000000012552 GJ
4 cal 0.000000016736 GJ
5 cal 0.00000002092 GJ
6 cal 0.000000025104 GJ
7 cal 0.000000029288 GJ
8 cal 0.000000033472 GJ
9 cal 0.000000037656 GJ
10 cal 0.00000004184 GJ
100 cal 0.0000004184 GJ
1,000 cal 0.000004184 GJ
10,000 cal 0.00004184 GJ
100,000 cal 0.000418 GJ
1,000,000 cal 0.004184 GJ
10,000,000 cal 0.04184 GJ
100,000,000 cal 0.4184 GJ
1,000,000,000 cal 4.184 GJ

More Calorie & Gigajoule Conversions