Calories to kJ Calculator – Convert Cal to Kilojoules (Free)
Free calories to kilojoules calculator — instantly convert cal to kJ or kJ to kcal. Includes formula, reference table, and kJ vs calories explained. Works for food labels
Calories to kJ Calculator: Convert Cal ↔ Kilojoules Instantly
Free bidirectional converter — enter kcal to get kJ, or enter kJ to get kcal. Formula, reference table, and kJ vs calories explained. Works for Australian, NZ, EU, and US food labels.
Kilojoules (kJ) and kilocalories (kcal) are both units of food energy. This calories to kilojoules converter works in both directions — enter kcal/Cal to get kJ, or enter kJ to get kcal. Also useful for kJ naar kcal (Dutch: kJ to kcal), and for Spanish speakers searching cal a kJ. Click any chip above for the most common values, or enter any value below for an instant conversion.
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kJ vs calories — what is the difference?
There are three related but distinct terms used in nutrition: calorie (cal), kilocalorie (kcal), and kilojoule (kJ). The small calorie (cal) is a scientific unit equal to the energy needed to raise 1 gram of water by 1°C — rarely used in everyday nutrition. The kilocalorie (kcal) equals 1,000 small calories — this is what food labels mean when they say "Calories." The kilojoule (kJ) is the SI (International System of Units) equivalent — used on food labels in Australia, New Zealand, the European Union, South Africa, and most of the world.
The confusion arises because the US writes "Calories" (capital C) on food labels, which actually means kilocalories (kcal) — not the small scientific calorie. In Australia and the EU, food labels show both kJ and kcal. When you see "8,700 kJ" on an Australian food label as the daily reference value, that is equivalent to approximately 2,079 kcal — close to the US 2,000 Calorie (kcal) daily reference. Understanding kilojoules vs calories is the foundation for reading any international food label correctly.
| Term | Symbol | Used where | Equal to |
|---|---|---|---|
| Small calorie | cal | Scientific contexts only | 1/1000 kcal |
| Kilocalorie | kcal | US / EU / nutrition science food labels | 1,000 cal = 4.184 kJ |
| Food Calorie | Cal (capital C) | US food labels | = 1 kcal = 4.184 kJ |
| Kilojoule | kJ | AU / NZ / EU / ZA food labels, science | = 0.239 kcal |
For all practical nutrition purposes: 1 Calorie = 1 kcal = 4.184 kJ. When converting food label values, always use kcal and kJ — not the small calorie (cal). The kJ vs calories distinction matters when reading international food packaging.
Calories to kJ formula — how to convert cal to kilojoules
1 kilocalorie (kcal) = 4.184 kilojoules (kJ). This is the internationally accepted thermochemical conversion factor — the same value used on all food labels worldwide. The kilojoules to kilocalories formula is simply the inverse.
How many kilocalories are in a kilojoule?
1 kJ = 0.2390 kcal (calculated as 1 ÷ 4.184 = 0.2390). Rounded: 1 kJ ≈ 0.24 kcal.
How many kJ are in 1 kcal / Calorie?
1 kcal = 4.184 kJ. 1 food Calorie (Cal) = 1 kcal = 4.184 kJ.
Worked examples — convert cal to kilojoules and kJ to kcal
- 2,000 kcal × 4.184 = 8,368 kJ (US daily reference)
- 8,700 kJ ÷ 4.184 = 2,079 kcal (AU/NZ daily reference)
- 500 kcal × 4.184 = 2,092 kJ
- 4,025 kJ ÷ 4.184 = 961.9 kcal ≈ 962 kcal (AU food label value)
- 400 kJ ÷ 4.184 = 95.6 kcal
kJ to kcal conversion table — common food label values
This reference table covers the most common kJ values on Australian, New Zealand, and EU food labels, converted to kilocalories (kcal / Calories). Use it as a quick lookup when reading food labels without a calculator. Click any row to load that value into the converter above.
| kJ | kcal | ≈ Food Cal | Notes |
|---|---|---|---|
| 50 | 11.9 | ~12 Cal | One small cracker |
| 100 | 23.9 | ~24 Cal | Small bite of food |
| 150 | 35.8 | ~36 Cal | |
| 200 | 47.8 | ~48 Cal | Small snack |
| 250 | 59.7 | ~60 Cal | |
| 300 | 71.7 | ~72 Cal | Light snack |
| 400 | 95.6 | ~96 Cal | Small yogurt |
| 500 | 119.5 | ~120 Cal | Small piece of fruit |
| 600 | 143.4 | ~143 Cal | |
| 700 | 167.3 | ~167 Cal | |
| 800 | 191.2 | ~191 Cal | |
| 900 | 215.1 | ~215 Cal | |
| 1,000 | 239.0 | ~239 Cal | Small meal component |
| 1,200 | 286.8 | ~287 Cal | |
| 1,500 | 358.5 | ~359 Cal | Light meal |
| 2,000 | 478.0 | ~478 Cal | Moderate meal |
| 2,500 | 597.5 | ~598 Cal | |
| 3,000 | 717.0 | ~717 Cal | Large meal |
| 4,000 | 956.0 | ~956 Cal | |
| 4,025 | 961.9 | ~962 Cal | AU daily reference ÷ ~2 |
| 5,000 | 1,195.0 | ~1,195 Cal | |
| 6,000 | 1,434.0 | ~1,434 Cal | |
| 7,000 | 1,673.0 | ~1,673 Cal | |
| 8,000 | 1,912.0 | ~1,912 Cal | |
| 8,700 | 2,079.1 | ~2,079 Cal | AU/NZ daily reference value |
| 10,000 | 2,390.0 | ~2,390 Cal |
Note that Australia and New Zealand use 8,700 kJ as the standard daily energy reference value on food labels — equivalent to approximately 2,079 kcal, very close to the US 2,000 Calorie (kcal) daily reference.
kcal to kJ conversion table — common calorie values to kilojoules
Convert common calorie (kcal) values to kilojoules with this quick reference table — useful for anyone tracking calories who needs the kJ equivalent for Australian or EU food labels.
| kcal (Calories) | kJ | Notes |
|---|---|---|
| 50 kcal | 209.2 kJ | |
| 100 kcal | 418.4 kJ | |
| 150 kcal | 627.6 kJ | |
| 200 kcal | 836.8 kJ | |
| 250 kcal | 1,046.0 kJ | |
| 300 kcal | 1,255.2 kJ | |
| 400 kcal | 1,673.6 kJ | |
| 500 kcal | 2,092.0 kJ | |
| 600 kcal | 2,510.4 kJ | |
| 750 kcal | 3,138.0 kJ | |
| 1,000 kcal | 4,184.0 kJ | |
| 1,200 kcal | 5,020.8 kJ | |
| 1,500 kcal | 6,276.0 kJ | |
| 1,800 kcal | 7,531.2 kJ | |
| 2,000 kcal | 8,368.0 kJ | US daily reference |
| 2,200 kcal | 9,204.8 kJ | |
| 2,500 kcal | 10,460.0 kJ | |
| 3,000 kcal | 12,552.0 kJ |
kJ naar kcal — kilojoules naar kilocalorieën (Dutch) · cal a kJ (Spanish)
🇳🇱 Dutch — kJ naar kcal omrekenen
Voor Nederlandstalige gebruikers — kJ naar kcal omrekenen (kilojoules naar kilocalorieën): gebruik de formule:
kcal = kJ ÷ 4,184Gebruik de rekenmachine hierboven voor een directe omrekening van kJ naar kcal. Voer het kJ-getal in en kies de richting "kJ → kcal".
(English: Use the formula kcal = kJ ÷ 4.184. Use the calculator above for an instant kJ naar kcal conversion.)
🇪🇸 Spanish — cal a kJ / kJ a cal
Para usuarios hispanohablantes — para convertir cal a kJ: usa la fórmula:
kJ = kcal × 4,184Para convertir kJ a cal: kcal = kJ ÷ 4,184. Usa la calculadora de arriba — funciona en todos los idiomas.
(English: To convert calories to kilojoules: use the formula kJ = kcal × 4.184.)
The converter above works for all languages — enter any value in kcal (Calories) or kJ for an instant result. No language settings needed.
How to read kJ on food labels — Australia, NZ, and EU
In Australia, New Zealand, and the European Union, food labels show energy in kilojoules (kJ) rather than — or alongside — kilocalories (kcal). If you are accustomed to counting calories in kcal, divide the kJ value by 4.184 to convert.
Practical food label examples
- Example 1 — Australian breakfast cereal: Label shows 1,500 kJ per serve → 1,500 ÷ 4.184 = 358.5 kcal ≈ 359 Cal
- Example 2 — EU chocolate bar: Label shows 2,200 kJ per 100g → 2,200 ÷ 4.184 = 525.9 kcal per 100g
- Example 3 — AU/NZ daily reference: 8,700 kJ = 2,079 kcal (versus the US 2,000 Cal/kcal daily reference)
| Country / Region | Reference | kJ | kcal |
|---|---|---|---|
| Australia / New Zealand | Standard adult daily | 8,700 kJ | 2,079 kcal |
| European Union | Standard adult daily | 8,400 kJ | 2,008 kcal |
| United States | Standard adult daily | 8,368 kJ | 2,000 kcal |
Calories to kJ — frequently asked questions
kJ = kcal × 4.184.kcal = kJ ÷ 4.184 for any kilojoules to kilocalories conversion.kJ = kcal × 4.184. To convert kJ to kcal: kcal = kJ ÷ 4.184. The factor 4.184 is the thermochemical calorie. Examples: 2,000 kcal × 4.184 = 8,368 kJ (US daily reference). 4,025 kJ ÷ 4.184 = 961.9 kcal. 500 kcal × 4.184 = 2,092 kJ. This kilojoules to kilocalories formula applies to all food energy conversions.More free nutrition and unit calculators on everycalcpro.com
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This is the most complete free calories to kJ converter available — covering both directions (kcal→kJ and kJ→kcal), a comprehensive reference table (50 kJ to 10,000 kJ), the kilojoules to kilocalories formula, kJ vs kcal vs Cal terminology, and food label guidance for Australia, New Zealand, and the EU. Multilingual coverage for Dutch (kJ naar kcal) and Spanish (cal a kJ) users is built in — enter any value in either language context and get an instant, accurate result. Use the free Calories to kJ Calculator above — enter any value for an instant conversion.