Gigajoule is 1000000000 joule units.
Gigajoules to Kilocalories Converter — GJ to kcal
Convert Gigajoule (GJ) to Kilocalorie (kcal) using the exact conversion factor (1 gigajoule = 239,005.7361 kilocalorie). See the formula, worked examples, and conversion table.
Gigajoules to Kilocalories converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
A kilocalorie is 1,000 calories.
Result = input x 1e+9 / 4184.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Gigajoules to Kilocalories
Gigajoule and Kilocalorie both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Gigajoule is 1000000000 joule units, and a kilocalorie is 1,000 calories.
Formula
kilocalories = gigajoules × 239005.736138
This factor comes from each unit's defined relationship to the category's base unit: 1 gigajoule equals 1000000000 base units, and 1 kilocalorie equals 4184 base units, so dividing one by the other gives the direct gigajoule-to-kilocalorie factor of 239005.736138.
Simple example
1 GJ × 239005.7361 = 239,005.7361 kcal
1 gigajoule = 239,005.7361 kilocalories.
Real-world example
100 GJ × 239005.7361 = 23,900,573.61 kcal
100 gigajoules = 23,900,573.61 kilocalories.
Conversion table
| Gigajoule (GJ) | Kilocalorie (kcal) |
|---|---|
| 1 GJ | 239,005.7361 kcal |
| 10 GJ | 2,390,057.361 kcal |
| 50 GJ | 11,950,286.81 kcal |
| 100 GJ | 23,900,573.61 kcal |
| 500 GJ | 119,502,868.1 kcal |
| 1,000 GJ | 239,005,736.1 kcal |
Reverse conversion: Kilocalorie to Gigajoule
1 kcal × 0.000004184 = 0.000004184 GJ
1 kilocalorie = 0.000004184 gigajoules.
gigajoules = kilocalories × 0.000004184
For a page dedicated to this direction, see Kilocalorie to Gigajoule.
Understanding the Gigajoule (GJ)
Gigajoule is 1000000000 joule units.
Understanding the Kilocalorie (kcal)
A kilocalorie is 1,000 calories.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilocalories are in 1 gigajoule?
1 gigajoule equals 239,005.7361 kilocalories, using the exact defined conversion factor rather than an estimate.
How do I convert gigajoule to kilocalorie?
Multiply the gigajoule value by 239005.7361. The converter above does this instantly to whatever precision you set.
How do I convert kilocalorie back to gigajoule?
Use the reverse factor: 1 kilocalorie equals 0.000004184 gigajoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a gigajoule?
Gigajoule (GJ) is a unit of engineering.
What is a kilocalorie?
Kilocalorie (kcal) is a unit of engineering.
Is the gigajoule to kilocalorie conversion exact?
Yes. Both gigajoule and kilocalorie are defined by fixed standards rather than physical artifacts, so the factor of 239005.7361 used above is exact to as many digits as you choose to display.
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.