Convert Kilojoules per Kilogram to Calories per Gram
Instantly convert Kilojoules per Kilogram (kJ/kg) to Calories per Gram (cal/g) with our free online calculator.
Formula: kJ/kg to cal/g — multiply by 0.239006
Reference Table
| Kilojoules per Kilogram (kJ/kg) | Calories per Gram (cal/g) |
|---|---|
| 1 | 0.239006 |
| 5 | 1.19503 |
| 10 | 2.39006 |
| 25 | 5.97514 |
| 50 | 11.9503 |
| 100 | 23.9006 |
How to Convert Kilojoules per Kilogram to Calories per Gram
Formula
To convert Kilojoules per Kilogram (kJ/kg) to Calories per Gram (cal/g): multiply by 0.239006
Step-by-Step
- Start with your value in Kilojoules per Kilogram (kJ/kg).
- Multiply by 0.239006 to perform the conversion.
- The result is your value expressed in Calories per Gram (cal/g).
Conversion Factor
1 kJ/kg = 0.239006 cal/g
Reverse Factor
1 cal/g = 4.184 kJ/kg
Worked Example
Convert 25 Kilojoules per Kilogram to Calories per Gram: 25 kJ/kg = 5.97514 cal/g
About Kilojoule per Kilogram (kJ/kg)
A metric specific-energy unit equal to exactly 1,000 J/kg. kJ/kg is the dominant working unit in thermodynamics for specific enthalpy h, specific internal energy u, and specific Gibbs/Helmholtz free energies (g, a) — all standard symbols in IAPWS-IF97 steam tables, NIST REFPROP property libraries, and CoolProp Helmholtz-energy fluid models. Reference values: saturated liquid water at 100°C (1 atm): h_f = 419.04 kJ/kg; saturated steam at same point: h_g = 2,676.05 kJ/kg; the latent heat of vaporization h_fg = 2,257.0 kJ/kg (the energy a low-pressure steam-heating system delivers when condensing). Refrigerant R-134a saturated liquid at 25°C: h_f ≈ 234.6 kJ/kg; saturated vapor: h_g ≈ 412.4 kJ/kg. Outside the US, food energy content on nutrition labels is reported as kJ/100g per EU Regulation 1169/2011 and Codex Alimentarius (typical: cooked white rice ~540 kJ/100g; olive oil ~3,700 kJ/100g; lean beef ~880 kJ/100g). HVAC design and combustion calculations per ASHRAE / VDI 4710 / EN 12831 routinely use kJ/kg for moist-air psychrometric enthalpy.
About Calorie per Gram (cal/g)
A CGS specific-energy unit equal to exactly 4,184 J/kg (using the thermochemical calorie definition per NIST SP 811), numerically identical to kcal/kg. cal/g is the working unit for chemistry reaction enthalpies per unit mass (heats of combustion measured in bomb calorimeters per ASTM D240 / D5865), food science nutritional energy (1 dietary 'Calorie' = 1 kcal = 1,000 cal — a confusing convention that persists despite ISO 80000-5 deprecation), thermochemistry per the NIST WebBook and Linstrom-Mallard NIST Standard Reference Database 69, and DSC (Differential Scanning Calorimetry) integration output for biological and pharmaceutical samples (TA Instruments, Mettler Toledo, PerkinElmer instruments default to cal/g for some legacy methods). Reference values per Atkins Physical Chemistry: water heat of vaporization at 100°C ≈ 540 cal/g; ice heat of fusion ≈ 80 cal/g; sucrose heat of combustion ≈ 3,940 cal/g; protein heat of combustion ≈ 4,100 cal/g; fats/oils ≈ 9,200 cal/g (the basis of the '9 calories per gram' nutritional rule of thumb for fat). Food labels outside the US showing 'kcal per 100g' display this unit scaled to a 100-gram serving size.
Quick Facts
- 1 Kilojoule per Kilogram equals 0.239006 Calories per Gram
- 1 Calorie per Gram equals 4.184 Kilojoules per Kilogram
- Kilojoule per Kilogram is a unit of specific energy
- Calorie per Gram is a unit of specific energy
- This conversion is commonly used in fuel comparison, battery technology, and rocket propulsion
- The Kilojoule per Kilogram belongs to the metric system
Common Kilojoule per Kilogram to Calorie per Gram Conversions
| Kilojoules per Kilogram (kJ/kg) | Calories per Gram (cal/g) |
|---|---|
| 0.01 | 0.00239006 |
| 0.1 | 0.0239006 |
| 0.25 | 0.0597514 |
| 0.5 | 0.119503 |
| 1 | 0.239006 |
| 2 | 0.478011 |
| 3 | 0.717017 |
| 5 | 1.19503 |
| 10 | 2.39006 |
| 15 | 3.58509 |
| 20 | 4.78011 |
| 25 | 5.97514 |
| 50 | 11.9503 |
| 75 | 17.9254 |
| 100 | 23.9006 |
| 250 | 59.7514 |
| 500 | 119.503 |
| 1000 | 239.006 |
| 5000 | 1195.03 |
| 10000 | 2390.06 |
Understanding Kilojoules per Kilogram
The Kilojoule per Kilogram (symbol: kJ/kg) is a unit of specific energy. A metric specific-energy unit equal to exactly 1,000 J/kg. kJ/kg is the dominant working unit in thermodynamics for specific enthalpy h, specific internal energy u, and specific Gibbs/Helmholtz free energies (g, a) — all standard symbols in IAPWS-IF97 steam tables, NIST REFPROP property libraries, and CoolProp Helmholtz-energy fluid models. Reference values: saturated liquid water at 100°C (1 atm): h_f = 419.04 kJ/kg; saturated steam at same point: h_g = 2,676.05 kJ/kg; the latent heat of vaporization h_fg = 2,257.0 kJ/kg (the energy a low-pressure steam-heating system delivers when condensing). Refrigerant R-134a saturated liquid at 25°C: h_f ≈ 234.6 kJ/kg; saturated vapor: h_g ≈ 412.4 kJ/kg. Outside the US, food energy content on nutrition labels is reported as kJ/100g per EU Regulation 1169/2011 and Codex Alimentarius (typical: cooked white rice ~540 kJ/100g; olive oil ~3,700 kJ/100g; lean beef ~880 kJ/100g). HVAC design and combustion calculations per ASHRAE / VDI 4710 / EN 12831 routinely use kJ/kg for moist-air psychrometric enthalpy.
It belongs to the metric measurement system.
Kilojoules per Kilogram are commonly used in fuel comparison, battery technology, and rocket propulsion.
Understanding Calories per Gram
The Calorie per Gram (symbol: cal/g) is a unit of specific energy. A CGS specific-energy unit equal to exactly 4,184 J/kg (using the thermochemical calorie definition per NIST SP 811), numerically identical to kcal/kg. cal/g is the working unit for chemistry reaction enthalpies per unit mass (heats of combustion measured in bomb calorimeters per ASTM D240 / D5865), food science nutritional energy (1 dietary 'Calorie' = 1 kcal = 1,000 cal — a confusing convention that persists despite ISO 80000-5 deprecation), thermochemistry per the NIST WebBook and Linstrom-Mallard NIST Standard Reference Database 69, and DSC (Differential Scanning Calorimetry) integration output for biological and pharmaceutical samples (TA Instruments, Mettler Toledo, PerkinElmer instruments default to cal/g for some legacy methods). Reference values per Atkins Physical Chemistry: water heat of vaporization at 100°C ≈ 540 cal/g; ice heat of fusion ≈ 80 cal/g; sucrose heat of combustion ≈ 3,940 cal/g; protein heat of combustion ≈ 4,100 cal/g; fats/oils ≈ 9,200 cal/g (the basis of the '9 calories per gram' nutritional rule of thumb for fat). Food labels outside the US showing 'kcal per 100g' display this unit scaled to a 100-gram serving size.
It belongs to the metric measurement system.
Calories per Gram are commonly used in fuel comparison, battery technology, and rocket propulsion.
Why Convert Kilojoules per Kilogram to Calories per Gram?
Converting between Kilojoules per Kilogram and Calories per Gram is a frequent requirement for engineers, scientists, and students working with specific energy 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 specific energy conversion is essential.
Frequently Asked Questions
How do I convert Kilojoules per Kilogram to Calories per Gram?
A metric specific-energy unit equal to exactly 1,000 J/kg. To convert Kilojoules per Kilogram to Calories per Gram, multiply by 0.239006. For example, 25 kJ/kg equals 5.97514 cal/g.
How many Calories per Gram are in 1 Kilojoule per Kilogram?
There are 0.239006 Calories per Gram in 1 Kilojoule per Kilogram.
How many Kilojoules per Kilogram are in 1 Calorie per Gram?
There are 4.184 Kilojoules per Kilogram in 1 Calorie per Gram.
What is the formula for Kilojoule per Kilogram to Calorie per Gram conversion?
The formula is: multiply by 0.239006. This means 1 kJ/kg = 0.239006 cal/g.
Is a Kilojoule per Kilogram bigger than a Calorie per Gram?
Yes. One Kilojoule per Kilogram is larger than one Calorie per Gram because 1 kJ/kg equals 0.239006 cal/g, which is less than 1.
When do you need to convert between Kilojoules per Kilogram and Calories per Gram?
A CGS specific-energy unit equal to exactly 4,184 J/kg (using the thermochemical calorie definition per NIST SP 811), numerically identical to kcal/kg. Kilojoule per Kilogram and Calorie per Gram are both specific energy 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.