Enter a material's mass, specific heat capacity, and temperature change to calculate the heat energy (ΔQ) absorbed or released. The Heat Capacity Calculator uses the formula ΔQ = c × m × ΔT to give you the total thermal energy in joules, kilojoules, and calories — plus a breakdown chart of the key variables.
Heat Energy (ΔQ)
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Heat Energy in Kilojoules
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Heat Energy in Calories
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Heat Energy in BTU
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Heat Capacity of Object (C = c × m)
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Heat capacity (also called thermal capacity) is the amount of heat energy required to raise the temperature of an object by one degree (1 K or 1°C). It depends on both the material (its specific heat) and the amount of that material (mass). The formula is C = c × m, where c is the specific heat capacity and m is the mass.
The heat transfer formula is ΔQ = c × m × ΔT, where ΔQ is the heat energy (in joules), c is the specific heat capacity (J/kg·K), m is the mass (kg), and ΔT is the temperature change (K or °C). A positive ΔQ means heat is absorbed (heating), while a negative ΔQ means heat is released (cooling).
Specific heat (c) is an intensive property — it describes a characteristic of the material itself, independent of how much of it you have. Heat capacity (C) is an extensive property — it describes a specific object and depends on both the material and its mass. Specific heat is measured in J/(kg·K), while heat capacity is measured in J/K.
Water has a specific heat capacity of approximately 4,186 J/(kg·K), which is among the highest of common substances. This means it takes 4,186 joules of energy to raise 1 kg of water by 1°C. Water's high heat capacity is why it is widely used as a coolant and why large bodies of water moderate regional climates.
Heat capacity is an extensive property, meaning it depends on the amount of substance present. The more mass an object has, the greater its heat capacity. Specific heat, by contrast, is an intensive property that remains constant regardless of the sample size.
Water's high heat capacity arises from its extensive hydrogen bonding network. A large amount of energy is required to break these bonds and increase molecular motion (temperature). This property allows water to absorb and store large amounts of thermal energy with only modest temperature changes.
The key conversions are: 1 calorie = 4.184 joules, 1 kilocalorie (kcal) = 4,184 joules, and 1 BTU ≈ 1,055.06 joules. This calculator automatically displays results in all four units (J, kJ, cal, and BTU) so you don't need to convert manually.
Yes. Simply enter a negative temperature change (ΔT) to calculate the heat energy released during cooling. For example, if a substance cools from 80°C to 20°C, enter ΔT = −60. The negative result indicates that energy is being lost by the substance to its surroundings.