A kilocalorie is 1,000 calories.
Kilocalories to Nanojoules Converter — kcal to nJ
Convert Kilocalorie (kcal) to Nanojoule (nJ) using the exact conversion factor (1 kilocalorie = 4.184e+12 nanojoule). See the formula, worked examples, and conversion table.
Kilocalories to Nanojoules converter
Converter
Energy Converter
Convert joules, calories, kilowatt-hours, BTU, electronvolts, therms, and mechanical work units.
Context values
Some unit families need one extra value for a physically accurate result.
Nanojoule is 1e-9 joule units.
Result = input x 4184 / 1e-9.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Kilocalories to Nanojoules
Kilocalorie and Nanojoule both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Specifically: A kilocalorie is 1,000 calories, and nanojoule is 1e-9 joule units.
Formula
nanojoules = kilocalories × 4.184e+12
This factor comes from each unit's defined relationship to the category's base unit: 1 kilocalorie equals 4184 base units, and 1 nanojoule equals 1e-9 base units, so dividing one by the other gives the direct kilocalorie-to-nanojoule factor of 4.184e+12.
Simple example
1 kcal × 4.184e+12 = 4.184e+12 nJ
1 kilocalorie = 4.184e+12 nanojoules.
Real-world example
100 kcal × 4.184e+12 = 4.184e+14 nJ
100 kilocalories = 4.184e+14 nanojoules.
Conversion table
| Kilocalorie (kcal) | Nanojoule (nJ) |
|---|---|
| 1 kcal | 4.184e+12 nJ |
| 10 kcal | 4.184e+13 nJ |
| 100 kcal | 4.184e+14 nJ |
| 500 kcal | 2.092e+15 nJ |
| 1,000 kcal | 4.184e+15 nJ |
| 2,000 kcal | 8.368e+15 nJ |
Reverse conversion: Nanojoule to Kilocalorie
4.184e+12 nJ × 2.390057e-13 = 1 kcal
4.184e+12 nanojoules = 1 kilocalorie.
kilocalories = nanojoules × 2.390057e-13
For a page dedicated to this direction, see Nanojoule to Kilocalorie.
Understanding the Kilocalorie (kcal)
A kilocalorie is 1,000 calories.
Understanding the Nanojoule (nJ)
Nanojoule is 1e-9 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many nanojoules are in 1 kilocalorie?
1 kilocalorie equals 4.184e+12 nanojoules, using the exact defined conversion factor rather than an estimate.
How do I convert kilocalorie to nanojoule?
Multiply the kilocalorie value by 4.184e+12. The converter above does this instantly to whatever precision you set.
How do I convert nanojoule back to kilocalorie?
Use the reverse factor: 1 nanojoule equals 2.390057e-13 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 energy.
What is a nanojoule?
Nanojoule (nJ) is a unit of energy.
Is the kilocalorie to nanojoule conversion exact?
Yes. Both kilocalorie and nanojoule are defined by fixed standards rather than physical artifacts, so the factor of 4.184e+12 used above is exact to as many digits as you choose to display.