Petajoule is 1000000000000000 joule units.
Petajoules to Kilocalories Converter — PJ to kcal
Convert Petajoule (PJ) to Kilocalorie (kcal) using the exact conversion factor (1 petajoule = 239,005,736,100 kilocalorie). See the formula, worked examples, and conversion table.
Petajoules 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+15 / 4184.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Petajoules to Kilocalories
Petajoule 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: Petajoule is 1000000000000000 joule units, and a kilocalorie is 1,000 calories.
Formula
kilocalories = petajoules × 239005736138
This factor comes from each unit's defined relationship to the category's base unit: 1 petajoule equals 1e+15 base units, and 1 kilocalorie equals 4184 base units, so dividing one by the other gives the direct petajoule-to-kilocalorie factor of 239005736138.
Simple example
1 PJ × 239005736100 = 239,005,736,100 kcal
1 petajoule = 239,005,736,100 kilocalories.
Real-world example
100 PJ × 239005736100 = 2.390057e+13 kcal
100 petajoules = 2.390057e+13 kilocalories.
Conversion table
| Petajoule (PJ) | Kilocalorie (kcal) |
|---|---|
| 1 PJ | 239,005,736,100 kcal |
| 10 PJ | 2.390057e+12 kcal |
| 50 PJ | 1.195029e+13 kcal |
| 100 PJ | 2.390057e+13 kcal |
| 500 PJ | 1.195029e+14 kcal |
| 1,000 PJ | 2.390057e+14 kcal |
Reverse conversion: Kilocalorie to Petajoule
1 kcal × 4.184e-12 = 4.184e-12 PJ
1 kilocalorie = 4.184e-12 petajoules.
petajoules = kilocalories × 4.184e-12
For a page dedicated to this direction, see Kilocalorie to Petajoule.
Understanding the Petajoule (PJ)
Petajoule is 1000000000000000 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 petajoule?
1 petajoule equals 239,005,736,100 kilocalories, using the exact defined conversion factor rather than an estimate.
How do I convert petajoule to kilocalorie?
Multiply the petajoule value by 239005736100. The converter above does this instantly to whatever precision you set.
How do I convert kilocalorie back to petajoule?
Use the reverse factor: 1 kilocalorie equals 4.184e-12 petajoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a petajoule?
Petajoule (PJ) is a unit of engineering.
What is a kilocalorie?
Kilocalorie (kcal) is a unit of engineering.
Is the petajoule to kilocalorie conversion exact?
Yes. Both petajoule and kilocalorie are defined by fixed standards rather than physical artifacts, so the factor of 239005736100 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.