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Heat calculator
Calculate the heat energy needed to change the temperature of a material, or work out a missing value.
Heat calculator
Enter your values below and press Calculate to see your result instantly.
Water: 4186 | Copper: 385 | Iron: 450
Total Thermal Energy (Q)
2.09 MJ
DAILY KWH EQ.
0.58 kWh
BTU RATING
1,981 BTU
The calculated energy is enough to boil approx 5.2 Liters of water from room temperature.
About the Heat calculator
Calculate the heat energy needed to change the temperature of a material, or work out a missing value.
How to use the Heat calculator
- Enter three of Mass (kg), Spec. Heat Capacity (J/kg·°C), Temp Change (ΔT °C) and Energy Input.
- Leave the one you want to find empty and press Calculate Energy.
Formula and method
Q = m × c × ΔT
Worked example
Heating 2 kg of water (4,186 J/kg·°C) by 30 °C needs 251,160 J.
Tips
- Specific heat of water is about 4,186 J/kg·°C.
- Divide joules by 3,600,000 to get kilowatt-hours.
Frequently asked questions
How long will it take to heat something?
Divide the heat energy by the heater power in watts to get seconds.