Calorimetry Heat Calculator (q = mcΔT)
Compute the heat energy (q) gained or lost by a substance from its mass, specific heat capacity, and temperature change using the calorimetry equation q = mcΔT.
g
J/g·°C
Temperature change input
°C
Heat absorbed (endothermic)
- 1
Temperature change ΔT
25 - 2
Heat energy q = m × c × ΔT
100 × 4.184 × 25 = 10,460
How does this calculator work?
Calorimetry heat is q = m × c × ΔT: multiply mass (g) by specific heat (J/g·°C) by temperature change (°C). A positive result means heat absorbed; negative means heat released. Water's specific heat is 4.184 J/g·°C. Enter ΔT directly or as Tf − Ti, and read q in joules and kilojoules.
Formula
How this is calculated
The mass (m) is the amount of substance being heated or cooled, in grams. The specific heat capacity (c) is the energy needed to raise one gram of the substance by one degree Celsius, in J/g·°C; liquid water is 4.184 J/g·°C by default. The temperature change (ΔT) can be entered directly, or calculated from the initial and final temperatures as ΔT = Tf − Ti.
The heat energy is q = m × c × ΔT. A positive q means heat is absorbed by the substance (temperature rises, endothermic from the substance's perspective), while a negative q means heat is released (temperature falls, exothermic). The result is shown in joules and kilojoules (1 kJ = 1000 J).
This equation assumes no phase change occurs over the temperature range (melting or boiling require latent-heat terms instead) and that the specific heat is constant. All temperatures use the same scale, so ΔT in °C equals ΔT in kelvin. Make sure mass is in grams to match the J/g·°C units of c.
Frequently asked questions
A negative heat value means the substance released energy because its final temperature was lower than its initial temperature (ΔT < 0). A positive q means the substance absorbed energy.
Liquid water has a specific heat of about 4.184 J/g·°C, which is the default. Ice and steam have different values (~2.09 and ~2.01 J/g·°C), and other substances vary widely.
No. q = mcΔT only covers heating or cooling within a single phase. Phase changes require adding latent heat (q = mL) separately.
Also known as
TG we-Calculate Editorial Team. (2026). Calorimetry Heat Calculator (q = mcΔT) [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/calorimetry-calculator
TG we-Calculate Editorial Team. "Calorimetry Heat Calculator (q = mcΔT)." TG we-Calculate. 2026. https://we-calculate.com/calculator/calorimetry-calculator.
TG we-Calculate Editorial Team, "Calorimetry Heat Calculator (q = mcΔT)," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/calorimetry-calculator
@misc{wecalculate_calorimetry_calculator, title = {Calorimetry Heat Calculator (q = mcΔT)}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/calorimetry-calculator}}, year = {2026}, note = {TG we-Calculate} }
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