Specific Heat Capacity Converter
Convert specific heat capacity between joule, kilojoule, calorie, kilocalorie, Btu, CHU and kilogram-force units per mass per degree. Enter a value, pick the units and read the result instantly.
Select two units to see the conversion factor.
Specific heat capacity is per unit mass. It is not total heat capacity (J/K for a whole object) and not molar heat capacity (J/(mol·K)); those need a mass or amount and are not converted here.
Specific Heat Capacity Formula
Specific heat capacity c is the heat Q needed to change the temperature of a mass m by ΔT: c = Q ÷ (m × ΔT), in J/(kg·K). Every unit is a fixed multiple of J/(kg·K). Result = value × (source factor ÷ target factor). Exact building blocks: 1 cal (IT) = 4.1868 J, 1 cal (th) = 4.184 J, 1 lb = 0.45359237 kg, 1 °F interval = 5/9 K, 1 Btu (IT) = 1,055.05585262 J, 1 kgf = 9.80665 N.
What Is Specific Heat Capacity?
Specific heat capacity is the amount of heat needed to raise the temperature of one unit of mass by one degree. Liquid water has about 4,186.8 J/(kg·K), which is why 1 cal/(g·°C) is the definition of the International Table calorie. Metals are much lower: copper is near 385 J/(kg·K).
It is different from heat capacity (J/K), which is the heat for a whole object and so depends on how much material there is, and from molar heat capacity (J/(mol·K)), which is per amount of substance. A 2 kg block of copper has a heat capacity of about 770 J/K, but its specific heat is still 385 J/(kg·K).
The “per degree” is a temperature interval, so kelvin and degree Celsius units are the same size and no offsets are used. A Fahrenheit or Rankine degree is only 5/9 of that, so a value per pound per °F is not equal to a value per gram per °C unless the mass units also differ; for example 1 cal/(g·°F) is 1.8 times the J/(kg·K) value of 1 cal/(g·°C). Calories and Btu come in IT and thermochemical versions, labelled in the list.
Supported Units
This converter supports the following 20 specific heat capacity units. The last column gives the value of each unit in the base unit J/(kg·K).
| Unit | Symbol | Value in J/(kg·K) |
|---|---|---|
| Joule per kilogram per kelvin | J/(kg·K) | 1 |
| Joule per kilogram per °C | J/(kg·°C) | 1 |
| Joule per gram per °C | J/(g·°C) | 1,000 |
| Kilojoule per kilogram per kelvin | kJ/(kg·K) | 1,000 |
| Kilojoule per kilogram per °C | kJ/(kg·°C) | 1,000 |
| Calorie (IT) per gram per °C | cal(IT)/(g·°C) | 4,186.8 |
| Calorie (IT) per gram per °F | cal(IT)/(g·°F) | 7,536.24 |
| Calorie (th) per gram per °C | cal(th)/(g·°C) | 4,184 |
| Kilocalorie (IT) per kilogram per °C | kcal(IT)/(kg·°C) | 4,186.8 |
| Kilocalorie (th) per kilogram per °C | kcal(th)/(kg·°C) | 4,184 |
| Kilocalorie (IT) per kilogram per kelvin | kcal(IT)/(kg·K) | 4,186.8 |
| Kilocalorie (th) per kilogram per kelvin | kcal(th)/(kg·K) | 4,184 |
| Kilogram-force meter per kilogram per kelvin | kgf·m/(kg·K) | 9.80665 |
| Pound-force foot per pound per °R | lbf·ft/(lb·°R) | 5.380320456 |
| Btu (IT) per pound per °F | Btu(IT)/(lb·°F) | 4,186.8 |
| Btu (th) per pound per °F | Btu(th)/(lb·°F) | 4,184 |
| Btu (IT) per pound per °R | Btu(IT)/(lb·°R) | 4,186.8 |
| Btu (th) per pound per °R | Btu(th)/(lb·°R) | 4,184 |
| Btu (IT) per pound per °C | Btu(IT)/(lb·°C) | 2,326 |
| CHU per pound per °C | CHU/(lb·°C) | 4,186.8 |
How to Use the Specific Heat Capacity Converter
- Type the specific heat capacity in the value box. Decimals and scientific notation such as 0.0025 or 2.5e-3 are accepted.
- Choose the From unit and the To unit.
- The result appears instantly, or press Convert Now. Very large or very small results are shown in scientific notation.
- Use Swap Units to reverse the conversion, Copy Result to copy the answer, open Show this value in all units for a full list, and Clear to start again.
Step-by-step by hand
- Find the size of each unit in the common base unit (J/(kg·K)): 1 J/(g·°C) = 1,000 J/(kg·K) and 1 Btu(IT)/(lb·°F) = 4,186.8 J/(kg·K).
- Divide the source size by the target size to get the conversion factor: 1,000 ÷ 4,186.8 = 0.2388458966, so 1 J/(g·°C) = 0.2388458966 Btu(IT)/(lb·°F).
- Multiply by your value: 0.385 J/(g·°C) × 0.2388458966 = 0.0919556702 Btu(IT)/(lb·°F).
Specific heat capacity is positive, so only zero and positive values are accepted.
Common Specific Heat Capacity Conversions
- Water: 1 cal/(g·°C) equals 4,186.8 J/(kg·K).
- Copper: 0.385 J/(g·°C) equals 0.0919556702 Btu/(lb·°F).
- Imperial to metric: 0.2 Btu/(lb·°F) equals 0.83736 kJ/(kg·K).
- Kilocalorie: 0.5 kcal/(kg·°C) equals 2,093.4 J/(kg·K).
- CHU: 1 CHU/(lb·°C) equals 4,186.8 J/(kg·K).
- Mechanical units: 1 kgf·m/(kg·K) equals 9.80665 J/(kg·K).
J/(kg·K) to Other Units
Quick reference for frequently used values
| J/(kg·K) | cal(IT)/(g·°C) | Btu(IT)/(lb·°F) | kJ/(kg·K) |
|---|---|---|---|
| 385 | 0.0919556702 | 0.0919556702 | 0.385 |
| 500 | 0.1194229483 | 0.1194229483 | 0.5 |
| 900 | 0.214961307 | 0.214961307 | 0.9 |
| 1,005 | 0.2400401261 | 0.2400401261 | 1.005 |
| 2,100 | 0.5015763829 | 0.5015763829 | 2.1 |
| 4,186.8 | 1 | 1 | 4.1868 |
Where and Why This Conversion Is Used
- Heating and cooling calculations: Q = m·c·ΔT needs consistent units.
- Materials data: tables list J/(g·°C), cal/(g·°C) or Btu/(lb·°F).
- Food and chemistry: heat of mixtures and calorimetry.
- Process and HVAC engineering: fluid heating and thermal storage.
Limitations
- Specific heat changes with temperature and with constant pressure versus constant volume; this tool converts units only.
- Water’s value of 1 cal/(g·°C) and 1 Btu/(lb·°F) is true only approximately and only for the IT versions.
- No conversion to total heat capacity or molar heat capacity is offered.
Important Differences Between Related Heat Quantities
- Specific heat capacity, J/(kg·K): energy needed to warm one kilogram of a material by one kelvin. It is not the total heat capacity of an object (J/K), which also depends on how much material there is, and it is not molar heat capacity (J/(mol·K)).
- Heat density, J/m²: heat or radiant energy delivered per unit area over a period. Heat flux density, W/m² is the rate of that transfer, energy per area per time. They are not interchangeable.
- Heat flux density, W/m² is heat flow per area. The heat transfer coefficient, W/(m²·K) is heat flux per kelvin of temperature difference, so heat flux = coefficient × temperature difference.
- Thermal conductivity, W/(m·K) is a material property. The heat transfer coefficient is a property of a surface or an assembly, and thermal resistance, K/W belongs to one specific object. Resistance is not conductivity or resistivity: R = L ÷ (k × A) for a slab.
- Temperature interval vs temperature: a difference of 10 °C is a difference of 18 °F. A reading of 10 °C is 50 °F. Every unit here that contains “per degree” or “K” uses intervals, so no offset is ever applied.
Each converter changes units within one quantity only. Related tools: Temperature Interval, Thermal Expansion, Thermal Resistance, Thermal Conductivity, Specific Heat Capacity, Heat Density, Heat Flux Density, Heat Transfer Coefficient, Fuel Efficiency - Mass and Fuel Efficiency - Volume.