Specific Heat Calculator
Calculate the heat energy needed to change a material’s temperature.
Please note: Results use idealised models — point masses, no air resistance, ideal gases and uniform materials. Real experiments deviate. Use these for study and estimation, not for engineering sign-off.
What the Specific Heat Calculator does
Specific heat capacity is the energy needed to raise one kilogram of a substance by one degree. Multiply it by the mass and the temperature change and you get the total heat required — the basis of every heating, cooling and thermal-storage calculation.
Formula
Q = m × c × ΔTΔT = Q ÷ (m × c)m = Q ÷ (c × ΔT)Time = Q ÷ Power
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Solve for | one of 3 options | Yes | — |
| Material | one of 13 options | Yes | — |
| Specific heat capacity | J/(kg·K) | In some modes | Accepts more than 0. Shown in 3 of the 39 modes. |
| Mass | number | In some modes | Shown in 26 of the 39 modes. |
| Mass unit | one of 6 options | In some modes | Shown in 26 of the 39 modes. |
| Temperature change | number | In some modes | Shown in 26 of the 39 modes. |
| Temperature change unit | one of 3 options | In some modes | Shown in 26 of the 39 modes. |
| Heat energy | number | In some modes | Shown in 26 of the 39 modes. |
| Heat energy unit | one of 8 options | In some modes | Shown in 26 of the 39 modes. |
| Heater power | number | Optional | Optional — gives the time the job would take. |
| Heater power unit | one of 4 options | Yes | — |
How to use it
- Choose Solve for and Material.
- Fill in the remaining inputs the form shows for your choice.
- Optionally add Heater power.
- Select Calculate.
Worked example
Heating 2 kg of water by 80 °C with a 2 kW heater.
- Material
- Water (4186 J/(kg·K))
- Mass
- 2 kg
- Temperature change
- 80
- Power
- 2000 W
Q = 2 × 4186 × 80 = 669,760 J, about 670 kJ or 0.186 kWh. At 2 kW that takes 334.9 seconds — roughly 5.6 minutes.
Frequently asked questions
Why does water take so much energy to heat?
Its specific heat of 4,186 J/(kg·K) is among the highest of any common substance, roughly ten times iron’s. Hydrogen bonding absorbs a great deal of energy before the temperature moves.
Does this cover boiling?
No. Boiling needs latent heat of vaporisation, which for water is 2.26 MJ/kg — far more than heating it from freezing to boiling in the first place.