Kilojoules to Calories Converter
Exercise times are estimates for a 70 kg adult.
100 kilojoules = 23.90 kcal, or about 24 Calories. The working is a single division: 100 ÷ 4.184 = 23.90.
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How To Convert 100 kJ To Calories
- Write down the kilojoules, here, 100.
- Divide by the conversion factor 4.184.
- The result, 23.90 kcal, is the same as 23.90 food Calories.
Shortcut: 100 × 0.239 = 23.9 kcal. Multiplying by 0.239 is the same as dividing by 4.184 to three decimal places.
Is 100 kJ A Lot?
At roughly 24 Calories, 100 kJ is the kind of figure printed on “diet” products, stock cubes, a splash of milk or a handful of salad leaves. It’s less than 2% of an average day’s energy.
- Carrot, medium (61 g), 105 kJ
- Tomato, medium (123 g), 92 kJ
- Tea with milk (250 ml), 84 kJ
- Broccoli, 1 cup chopped (91 g), 130 kJ
Values are typical, the food kJ chart lists 120+ foods.
100 kJ On A Food Label
A label line that reads “100 kJ per serve” only tells half the story. Divide by the serve size and you get the energy density, how much energy is packed into every 100 g of the food.
| Serving size | kJ per 100 g | kcal per 100 g | Energy density |
|---|---|---|---|
| 25 g serve | 400 kJ | 96 kcal | low |
| 40 g serve | 250 kJ | 60 kcal | low |
| 60 g serve | 167 kJ | 40 kcal | very low |
| 100 g serve | 100 kJ | 24 kcal | very low |
| 150 g serve | 67 kJ | 16 kcal | very low |
| 250 g serve | 40 kJ | 10 kcal | very low |
Take a 60 g serve: 100 kJ ÷ 60 × 100 = 167 kJ per 100 g, which puts it in the very low-density group alongside salad vegetables, berries and clear soups. Scale any pack to your portion with the food label calculator.
100 kJ In Your Meals
Here’s 100 kJ measured against meal-sized budgets for a lighter, average and more active day:
| Meal budget | 6,300 kJ day | 8,700 kJ day | 10,500 kJ day |
|---|---|---|---|
| Breakfast (25%) | 6% | 5% | 4% |
| Lunch (30%) | 5% | 4% | 3% |
| Dinner (35%) | 5% | 3% | 3% |
| Snacks (10%) | 16% | 11% | 10% |
How Long Does It Take To Burn 100 kJ?
| Activity | 60 kg person | 70 kg person | 85 kg person |
|---|---|---|---|
| Walking, moderate (5 km/h) | 7 min | 6 min | 5 min |
| Jogging (8 km/h) | 3 min | 2 min | 2 min |
| Cycling, moderate | 3 min | 3 min | 2 min |
| Swimming, moderate laps | 4 min | 3 min | 3 min |
At 70 kg you’d use up 100 kJ in about 6 min of walking: or 2 min if you jog. Check other activities in the exercise kJ calculator.
100 kJ As Part Of Your Day
| Daily intake | Share used by 100 kJ |
|---|---|
| 5,021 kJ (1,200 kcal) weight-loss plan | 2% |
| 6,276 kJ (1,500 kcal) plan | 1.6% |
| 8,368 kJ (2,000 kcal) US/UK/EU reference | 1.2% |
| 8,700 kJ AU/NZ label reference | 1.1% |
| 10,460 kJ (2,500 kcal) active adult | 1% |
100 kJ In Other Energy Units
| Unit | Value |
|---|---|
| Kilojoules (kJ) | 100 kJ |
| Calories / kilocalories (kcal) | 23.90 kcal |
| Small calories (cal) | 23,901 cal |
| Joules (J) | 100,000 J |
| Megajoules (MJ) | 0.1 MJ |
| Watt-hours (Wh) | 27.8 Wh |
Nearby kJ To Calories Conversions
FAQ
How many Calories are in 100 kJ?
100 kJ is 23.90 Calories (kcal). Divide the kilojoules by 4.184 to convert.
Is 100 kJ the same as 24 kcal?
Almost exactly: 100 kJ is 23.90 kcal, which rounds to 24 kcal.
Is 100 kJ a lot?
No, 100 kJ is a very small amount, under 2% of an average day.
How much walking burns 100 kJ?
Roughly 6 min on foot for a 70 kg person; an 85 kg person needs about 5 min.
What if a food has 100 kJ per 100 g?
Then it has 23.9 kcal per 100 g, which is a very low-density food. A 30 g handful would provide about 30 kJ (7 kcal).