Specific Heat Calculator
Calculate heat energy absorbed or released, temperature change, or specific heat capacity using Q = mcΔT.
Supports metric and imperial units.
The specific heat formula is one of the most fundamental equations in thermodynamics. It relates the heat energy transferred to or from an object to its mass, its specific heat capacity, and the temperature change it undergoes.
The formula: Q = m × c × ΔT
Where:
- Q = Heat energy transferred (Joules, J or calories, cal)
- m = Mass of the substance (kg or g)
- c = Specific heat capacity (J/kg·°C or J/g·°C)
- ΔT = Temperature change (°C or °F, where ΔF = ΔC × 9/5)
Rearranged to solve for each variable:
- Temperature change: ΔT = Q ÷ (m × c)
- Specific heat: c = Q ÷ (m × ΔT)
- Mass: m = Q ÷ (c × ΔT)
Specific heat capacities of common materials:
| Material | Specific Heat (J/g·°C) |
|---|---|
| Liquid water | 4.186 |
| Ice | 2.09 |
| Steam | 2.01 |
| Aluminum | 0.897 |
| Iron / Steel | 0.449 |
| Copper | 0.385 |
| Gold | 0.129 |
| Glass | 0.84 |
| Wood (typical) | 1.76 |
| Air | 1.005 |
| Ethanol | 2.44 |
Why water has a high specific heat: Water’s specific heat (4.186 J/g·°C) is exceptionally high compared to most substances. This means it takes a lot of energy to heat water — which is why it is used as a coolant in engines, why coastal areas have milder climates than inland areas, and why the human body (which is ~60% water) maintains stable temperature despite metabolic heat production.
Practical example (metric): How much energy is needed to heat 500g of water from 20°C to 100°C? Q = 500 × 4.186 × (100 − 20) = 500 × 4.186 × 80 = 167,440 J (167.4 kJ)
Practical example (imperial): 1 BTU is defined as the heat needed to raise 1 pound of water by 1°F. To heat 2 lbs of water by 50°F: Q = 2 × 1 × 50 = 100 BTU
Unit conversions:
- 1 calorie = 4.184 J
- 1 BTU = 1,055 J = 252.2 calories
- 1 kJ = 1,000 J