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Convert Kilojoules per Kelvin to Calories per Kelvin

Instantly convert Kilojoules per Kelvin (kJ/K) to Calories per Kelvin (cal/K) with our free online calculator.

Reviewed by Christopher FloiedUpdated

Formula: kJ/K to cal/Kmultiply by 239.006

Reference Table

Kilojoules per Kelvin (kJ/K)Calories per Kelvin (cal/K)
1239.006
51195.03
102390.06
255975.14
5011950.3
10023900.6

How to Convert Kilojoules per Kelvin to Calories per Kelvin

Formula

To convert Kilojoules per Kelvin (kJ/K) to Calories per Kelvin (cal/K): multiply by 239.006

Step-by-Step

  1. Start with your value in Kilojoules per Kelvin (kJ/K).
  2. Multiply by 239.006 to perform the conversion.
  3. The result is your value expressed in Calories per Kelvin (cal/K).

Conversion Factor

1 kJ/K = 239.006 cal/K

Reverse Factor

1 cal/K = 0.004184 kJ/K

Worked Example

Convert 25 Kilojoules per Kelvin to Calories per Kelvin: 25 kJ/K = 5975.14 cal/K

About Kilojoule per Kelvin (kJ/K)

A metric entropy unit equal to exactly 1,000 J/K. kJ/K is the practical working unit for industrial/plant-scale thermodynamic analysis where total entropy flows are large enough that J/K becomes unwieldy: steam-power-plant Rankine-cycle second-law (exergy) evaluations per ASME PTC 4 / VDI 4655 / IEC 60953 standards, large refrigeration-cycle COP optimization (Carnot-to-actual entropy generation comparisons for chillers > 1 MW cooling capacity), industrial combustion entropy balances (cement-kiln Cl-Pre-Calciner systems, glass-furnace regenerators, blast-furnace iron-reduction processes), and gas-turbine combined-cycle (CCGT) plant heat-balance diagrams per IEC 60534. A typical 600 MW supercritical coal-fired power station rejects entropy at ~3,000 kJ/(K·s) to its cooling tower; nuclear PWR steam-generator secondary-side entropy generation ~5,000 kJ/(K·s); industrial-scale ammonia-synthesis (Haber-Bosch) reactor entropy generation ~50 kJ/(K·s). The kJ/K unit is dominant in EBSILON Professional, Aspen Plus, GateCycle, and Thermoflex cycle-simulation software output reports.

About Calorie per Kelvin (cal/K)

A CGS entropy unit equal to exactly 4.184 J/K (using the thermochemical calorie definition per NIST SP 811). cal/K is a legacy unit that persists in older chemistry and biochemistry literature, with the equivalent molar form cal/(K·mol) (often abbreviated 'e.u.' for 'entropy unit' in older textbooks) appearing routinely in: classical physical-chemistry references pre-1980 (Lewis-Randall, Pitzer-Brewer thermodynamics texts), biochemistry literature on protein-folding entropy (typical ΔS_folding ranges from -50 to +50 cal/(K·mol) per residue), enzymology free-energy diagrams (Eyring-transition-state analysis), and pharmaceutical drug-binding thermodynamics (isothermal titration calorimetry / ITC papers in J. Mol. Biol., Biochemistry, Protein Sci. through the 1990s). The bond-dissociation entropy of H₂(g) → 2H(g) at 298 K is ΔS° = +24.4 cal/(K·mol). Modern publications increasingly use SI J/K, but cal/K appears in cross-references to older databases (NIST WebBook still dual-lists), in NMR-relaxation thermodynamic-cycle interpretation, and in physical-organic-chemistry literature where Arrhenius pre-exponential factors are quoted with entropy in cal-units.

Quick Facts

  • 1 Kilojoule per Kelvin equals 239.006 Calories per Kelvin
  • 1 Calorie per Kelvin equals 0.004184 Kilojoules per Kelvin
  • Kilojoule per Kelvin is a unit of entropy
  • Calorie per Kelvin is a unit of entropy
  • This conversion is commonly used in thermodynamics, refrigeration cycles, and chemical engineering
  • The Kilojoule per Kelvin belongs to the metric system

Common Kilojoule per Kelvin to Calorie per Kelvin Conversions

Kilojoules per Kelvin (kJ/K)Calories per Kelvin (cal/K)
0.012.39006
0.123.9006
0.2559.7514
0.5119.503
1239.006
2478.011
3717.017
51195.03
102390.06
153585.09
204780.11
255975.14
5011950.3
7517925.4
10023900.6
25059751.4
500119503
1000239006
50001195030
100002390060

Understanding Kilojoules per Kelvin

The Kilojoule per Kelvin (symbol: kJ/K) is a unit of entropy. A metric entropy unit equal to exactly 1,000 J/K. kJ/K is the practical working unit for industrial/plant-scale thermodynamic analysis where total entropy flows are large enough that J/K becomes unwieldy: steam-power-plant Rankine-cycle second-law (exergy) evaluations per ASME PTC 4 / VDI 4655 / IEC 60953 standards, large refrigeration-cycle COP optimization (Carnot-to-actual entropy generation comparisons for chillers > 1 MW cooling capacity), industrial combustion entropy balances (cement-kiln Cl-Pre-Calciner systems, glass-furnace regenerators, blast-furnace iron-reduction processes), and gas-turbine combined-cycle (CCGT) plant heat-balance diagrams per IEC 60534. A typical 600 MW supercritical coal-fired power station rejects entropy at ~3,000 kJ/(K·s) to its cooling tower; nuclear PWR steam-generator secondary-side entropy generation ~5,000 kJ/(K·s); industrial-scale ammonia-synthesis (Haber-Bosch) reactor entropy generation ~50 kJ/(K·s). The kJ/K unit is dominant in EBSILON Professional, Aspen Plus, GateCycle, and Thermoflex cycle-simulation software output reports.

It belongs to the metric measurement system.

Kilojoules per Kelvin are commonly used in thermodynamics, refrigeration cycles, and chemical engineering.

Understanding Calories per Kelvin

The Calorie per Kelvin (symbol: cal/K) is a unit of entropy. A CGS entropy unit equal to exactly 4.184 J/K (using the thermochemical calorie definition per NIST SP 811). cal/K is a legacy unit that persists in older chemistry and biochemistry literature, with the equivalent molar form cal/(K·mol) (often abbreviated 'e.u.' for 'entropy unit' in older textbooks) appearing routinely in: classical physical-chemistry references pre-1980 (Lewis-Randall, Pitzer-Brewer thermodynamics texts), biochemistry literature on protein-folding entropy (typical ΔS_folding ranges from -50 to +50 cal/(K·mol) per residue), enzymology free-energy diagrams (Eyring-transition-state analysis), and pharmaceutical drug-binding thermodynamics (isothermal titration calorimetry / ITC papers in J. Mol. Biol., Biochemistry, Protein Sci. through the 1990s). The bond-dissociation entropy of H₂(g) → 2H(g) at 298 K is ΔS° = +24.4 cal/(K·mol). Modern publications increasingly use SI J/K, but cal/K appears in cross-references to older databases (NIST WebBook still dual-lists), in NMR-relaxation thermodynamic-cycle interpretation, and in physical-organic-chemistry literature where Arrhenius pre-exponential factors are quoted with entropy in cal-units.

It belongs to the metric measurement system.

Calories per Kelvin are commonly used in thermodynamics, refrigeration cycles, and chemical engineering.

Why Convert Kilojoules per Kelvin to Calories per Kelvin?

Converting between Kilojoules per Kelvin and Calories per Kelvin is a frequent requirement for engineers, scientists, and students working with entropy values. Different industries and regions favour different unit systems, so having a dependable conversion tool saves time and prevents errors in technical calculations. Whether you are verifying a specification sheet, cross-checking simulation results, or preparing a report for an international audience, accurate entropy conversion is essential.

Frequently Asked Questions

How do I convert Kilojoules per Kelvin to Calories per Kelvin?

A metric entropy unit equal to exactly 1,000 J/K. To convert Kilojoules per Kelvin to Calories per Kelvin, multiply by 239.006. For example, 25 kJ/K equals 5975.14 cal/K.

How many Calories per Kelvin are in 1 Kilojoule per Kelvin?

There are 239.006 Calories per Kelvin in 1 Kilojoule per Kelvin.

How many Kilojoules per Kelvin are in 1 Calorie per Kelvin?

There are 0.004184 Kilojoules per Kelvin in 1 Calorie per Kelvin.

What is the formula for Kilojoule per Kelvin to Calorie per Kelvin conversion?

The formula is: multiply by 239.006. This means 1 kJ/K = 239.006 cal/K.

Is a Kilojoule per Kelvin bigger than a Calorie per Kelvin?

No. One Kilojoule per Kelvin is smaller than one Calorie per Kelvin because 1 kJ/K equals 239.006 cal/K, which is greater than 1.

When do you need to convert between Kilojoules per Kelvin and Calories per Kelvin?

A CGS entropy unit equal to exactly 4. Kilojoule per Kelvin and Calorie per Kelvin are both entropy units, so conversion comes up whenever one source of information uses one unit and another uses the other — a classic cross-reference challenge in engineering, trade, travel, and everyday life.

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