A kilocalorie is 1,000 calories.
Kilocalories to Exajoules Converter — kcal to EJ
Convert Kilocalorie (kcal) to Exajoule (EJ) using the exact conversion factor (1 kilocalorie = 4.184e-15 exajoule). See the formula, worked examples, and conversion table.
Kilocalories to Exajoules 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.
Exajoule is 1000000000000000000 joule units.
Result = input x 4184 / 1e+18.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Kilocalories to Exajoules
Kilocalorie and Exajoule 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: A kilocalorie is 1,000 calories, and exajoule is 1000000000000000000 joule units.
Formula
exajoules = kilocalories × 4.184e-15
This factor comes from each unit's defined relationship to the category's base unit: 1 kilocalorie equals 4184 base units, and 1 exajoule equals 1e+18 base units, so dividing one by the other gives the direct kilocalorie-to-exajoule factor of 4.184e-15.
Simple example
1 kcal × 4.184e-15 = 4.184e-15 EJ
1 kilocalorie = 4.184e-15 exajoules.
Real-world example
100 kcal × 4.184e-15 = 4.184e-13 EJ
100 kilocalories = 4.184e-13 exajoules.
Conversion table
| Kilocalorie (kcal) | Exajoule (EJ) |
|---|---|
| 1 kcal | 4.184e-15 EJ |
| 10 kcal | 4.184e-14 EJ |
| 50 kcal | 2.092e-13 EJ |
| 100 kcal | 4.184e-13 EJ |
| 500 kcal | 2.092e-12 EJ |
| 1,000 kcal | 4.184e-12 EJ |
Reverse conversion: Exajoule to Kilocalorie
4.184e-15 EJ × 2.390057e+14 = 1 kcal
4.184e-15 exajoules = 1 kilocalorie.
kilocalories = exajoules × 2.390057e+14
For a page dedicated to this direction, see Exajoule to Kilocalorie.
Understanding the Kilocalorie (kcal)
A kilocalorie is 1,000 calories.
Understanding the Exajoule (EJ)
Exajoule is 1000000000000000000 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many exajoules are in 1 kilocalorie?
1 kilocalorie equals 4.184e-15 exajoules, using the exact defined conversion factor rather than an estimate.
How do I convert kilocalorie to exajoule?
Multiply the kilocalorie value by 4.184e-15. The converter above does this instantly to whatever precision you set.
How do I convert exajoule back to kilocalorie?
Use the reverse factor: 1 exajoule equals 2.390057e+14 kilocalories. You can also use the swap control in the converter above to flip the direction instantly.
What is a kilocalorie?
Kilocalorie (kcal) is a unit of engineering.
What is a exajoule?
Exajoule (EJ) is a unit of engineering.
Is the kilocalorie to exajoule conversion exact?
Yes. Both kilocalorie and exajoule are defined by fixed standards rather than physical artifacts, so the factor of 4.184e-15 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.