The heat energy required to change a substance’s temperature depends on its mass, specific heat capacity, and the size of the temperature change.
How it works
The formula Q = m × c × ΔT relates the four quantities; choosing which one to solve for rearranges the same equation around the other three known values.
What this does not include
This does not include a built-in table of specific heat values — enter the substance’s known specific heat capacity directly, since no fixed table could keep pace with every material.
How to use this calculator
- Choose what to solve for, then enter the known values.
A worked example
100 g of water (specific heat 4.186 J/g°C) heated by 20°C: heat required = m×c×ΔT = 100 × 4.186 × 20 = 8,372 J.
Given 8,372 J applied to the same 100 g of water, the temperature change works out to 20°C — the reverse calculation.
What the variables mean
| Variable | Meaning |
|---|---|
| Mass | Mass of the substance |
| Specific heat | Energy needed to raise 1 gram by 1°C, unique to each material |
| ΔT (delta T) | Temperature change |
Edge cases worth knowing
Water has an unusually high specific heat compared to most materials — which is exactly why it takes so much energy to heat (or cool) water, and why it’s used as a coolant and for climate moderation near large bodies of water.
A specific heat of zero has no physical meaning, so the calculator declines to show a result for that input.
Frequently asked questions
Why does water have such a high specific heat?
Water requires an unusually large amount of energy to change temperature compared to most substances, which is why it’s commonly used as a coolant and why large bodies of water moderate nearby climates.
What are the units of specific heat capacity?
Commonly joules per gram per degree Celsius (J/g°C), representing how much energy is needed to raise one gram of the substance by one degree.
What’s a practical use for this formula?
Calculating how much energy is needed to heat a liquid, or figuring out a substance’s final temperature after adding a known amount of heat.
