Specific heat converter
Type a specific heat capacity, choose the units, and see the result plus the same value in every common unit. The calorie and BTU used here are the International Table (IT) ones, stated below.
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How to use it
- Type a number. A dot or a comma works as the decimal separator.
- Choose the unit you have and the unit you need. The ⇄ button swaps them.
- The table shows the same specific heat in all common units at once.
Conversion factors
Every unit is converted through J/(kg·K).
| Unit |
In J/(kg·K) |
| 1 kJ/(kg·K) |
1,000 |
| 1 J/(g·K) |
1,000 |
| 1 cal/(g·°C) (IT) |
4,186.8 |
| 1 kcal/(kg·°C) (IT) |
4,186.8 |
| 1 BTU/(lb·°F) (IT) |
4,186.8 |
The BTU value comes from 1,055.05585262 J ÷ (0.45359237 kg × 5/9 K), because a Fahrenheit degree is 5/9 of a kelvin.
Worked example
A material is listed at 0.9 kJ/(kg·K). That is 900 J/(kg·K), or 900 ÷ 4,186.8 = 0.215 BTU/(lb·°F). Warming 2 kg of it by 10 K takes 900 × 2 × 10 = 18,000 J.
Tips
- Specific heat varies with temperature; quoted values are for a stated temperature range.
- Molar heat capacity, in J/(mol·K), is a different quantity and needs the molar mass.
Frequently asked questions
Which calorie and BTU does this converter use?
The International Table (IT) calorie of 4.1868 J and the IT BTU of 1,055.05585262 J. The thermochemical calorie is 4.184 J, which would shift results by about 0.07%.
Why are cal/(g·°C) and BTU/(lb·°F) the same number?
By definition. The IT BTU per pound per degree Fahrenheit works out to exactly 4,186.8 J/(kg·K), the same as one IT calorie per gram per degree Celsius.
How many J/(kg·K) is the specific heat of water?
About 4,186 J/(kg·K) near room temperature, or roughly 1 cal/(g·°C). The exact value changes slightly with temperature.
Is a temperature difference of 1 K the same as 1 °C?
Yes. Specific heat is per degree of temperature change, and a change of 1 K equals a change of 1 °C, so those units can be swapped freely.