How many attojoule in 1 kilocalorie?
The answer is 4.1858E+21.
We assume you are converting between attojoule and kilocalorie [15 °C].
You can view more details on each measurement unit: attojoule or
kilocalorie
The SI derived unit for energy is the joule.
1 joule is equal to 1.0E+18 attojoule, or 0.00023890295761862 kilocalorie.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between attojoules and kilocalories.
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You can do the reverse unit conversion from
kilocalorie to attojoule, or enter any two units below:

The SI prefix "atto" represents a factor of
10^{-18}, or in exponential notation, 1E-18.

So 1 attojoule = 10^{-18} joules.

The definition of a joule is as follows:

The joule (symbol J, also called newton meter, watt second, or coulomb volt) is the SI unit of energy and work. The unit is pronounced to rhyme with "tool", and is named in honor of the physicist James Prescott Joule (1818-1889).

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