Kilojoules (kJ) to Kilocalories (kcal) Converter
Convert food energy from Kilojoules to Calories (kcal). Includes serving size calculator and common food energy database. Essential for diet and nutrition planning.
Energy Converter
About
Global food labeling standards are divided. While the United States relies on the "Calorie" (technically the kilocalorie or kcal), most of Europe, Australia, and scientific communities use the Kilojoule (kJ) as the standard unit of energy. This creates confusion for consumers attempting to track intake across imported foods or international diet plans.
This tool bridges that gap by applying the strict thermochemical definition where 1 kcal exactly equals 4.184 kJ. Unlike simple converters, this tool allows users to input data directly from the nutrition label - typically given per 100g - and calculate the specific caloric content of their actual serving size. This context is vital for diabetics, athletes, and anyone maintaining a caloric deficit.
Formulas
The conversion factor is derived from the specific heat capacity of water. To convert Kilojoules to Kilocalories, we divide by the constant factor.
To calculate the energy of a specific serving size when the label lists value per 100g:
Reference Data
| Food Item (100g) | Energy (kJ) | Energy (kcal) | Typical Serving |
|---|---|---|---|
| Apple (Raw) | 218 kJ | 52 kcal | 1 Medium (180g) |
| Banana | 371 kJ | 89 kcal | 1 Medium (120g) |
| Broccoli | 141 kJ | 34 kcal | 1 Cup (90g) |
| Chicken Breast (Cooked) | 690 kJ | 165 kcal | 1 Fillet (150g) |
| White Rice (Cooked) | 544 kJ | 130 kcal | 1 Cup (160g) |
| Cheddar Cheese | 1,680 kJ | 402 kcal | 1 Slice (30g) |
| Almonds | 2,420 kJ | 579 kcal | 1 Handful (30g) |
| Olive Oil | 3,700 kJ | 884 kcal | 1 Tbsp (14g) |
| Milk (Whole) | 252 kJ | 60 kcal | 1 Glass (250g) |