Heat Capacity Calculator
Enter the heat energy added and the temperature change to get the heat capacity of a whole object in joules per kelvin — the energy it stores for each degree.
One value, two inputs
Enter the heat energy in joules and the temperature change in kelvin, and the calculator returns the heat capacity of the object in joules per kelvin.
Use SI units
Joules for energy and kelvin for the temperature change give a heat capacity in J/K. A change of 1 K equals a change of 1 °C.
What is heat capacity?
Energy stored per degree
This heat capacity calculator finds how much heat energy an object stores for each degree of temperature change. Heat capacity is the energy in joules needed to raise the temperature of the whole object by one kelvin. It depends on both the material and how much of it there is, which is why a large kettle of water takes far more energy to heat than a small cup. Enter the heat added and the temperature change, and the calculator returns the value in joules per kelvin.
Divide the heat energy by the temperature change to get the heat capacity of the object in J/K.
The heat capacity is the heat energy added divided by the temperature change it produces.
C = Q ÷ ΔTHere Q is the heat energy in joules and ΔT is the temperature change in kelvin. The result is the energy the object needs for each degree. A high value means the object soaks up a lot of heat for a small temperature rise; a low value means it heats up quickly. Heat capacity scales with size: double the mass of the same material and you double the heat capacity.
Suppose you add 4184 J of heat to a small object and its temperature rises by 10 K.
Take the temperature change
ΔT = 10 K — the rise in temperature the heat produced.
Divide the heat energy by that change
4184 ÷ 10 = 418.4 — the heat energy spread over each degree.
Read the heat capacity
C = 418.4 J/K — the object stores 418.4 joules for every degree it warms.
The formula is exact, but a few practical points are worth keeping in mind.
Heat capacity is for the whole object, not per kilogram
Heat capacity (C, in J/K) describes a specific object and depends on how much material it contains, so a bigger object has a bigger heat capacity. That is different from specific heat capacity (c, in J/(kg·K)), which is per kilogram and depends only on the substance — divide the heat capacity by the mass to get it. This calculator also assumes the value stays constant over the range and that no phase change (melting or boiling) happens. Keep your units consistent — joules and kelvin — or the result will be wrong; a change in kelvin equals the same change in degrees Celsius, but never in Fahrenheit.