Why Convert Kilojoules to Kilocalories?
Converting between kilojoules (kJ) and kilocalories (kcal) is one of the most common energy conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert kJ to kcal saves time and prevents errors.
Energy conversions between kJ and kcal are important for nutrition, electricity costs, and engineering. Food labels in different countries use different energy units — China and the EU use kilojoules (kJ), while the US and Australia use Calories (kcal). Understanding kWh-to-joule conversions helps calculate electricity costs and compare energy efficiency of appliances. In HVAC, BTU ratings are standard in North America while watts or kilowatts are used elsewhere.
How to Convert Kilojoules to Kilocalories
To convert kilojoules to kilocalories, use the following formula:
kcal = kJ × 0.2390057361
Example: 1 kJ = 0.2390057361 kcal
For example, 5 kJ = 1.195028681 kcal, 10 kJ = 2.390057361 kcal, and 100 kJ = 23.90057361 kcal. Our calculator above performs this conversion instantly with full precision — no rounding errors.
Common Use Cases
- Daily calorie intake (2000 kcal): 8368 kJ = 2000 kcal
- A bowl of cooked white rice: 837 kJ = 200.0478011 kcal
- 30 minutes of running: 1255 kJ = 299.9521989 kcal
- A Big Mac hamburger: 2301 kJ = 549.9521989 kcal
- Recommended intake for an active male: 4184 kJ = 1000 kcal
Common Mistakes to Avoid
- Calorie vs kilocalorie: Food labels in the US show "Calories" (capital C) which are actually kilocalories (kcal). 1 food Calorie = 1 kcal = 4.184 kJ.
- kWh is not kW: Kilowatt-hours (kWh) measure energy consumed over time, while kilowatts (kW) measure instantaneous power. Don't confuse them.
- Regional food labels: China/EU labels use kilojoules (kJ), US/Australia use Calories (kcal). Check which system before comparing.
Pro Tips
- Memorize the factor: 1 kJ = 0.2390057361 kcal. For quick mental math, remember this base conversion.
- Quick reference: 5 kJ = 1.195028681 kcal · 10 kJ = 2.390057361 kcal · 25 kJ = 5.975143403 kcal · 50 kJ = 11.95028681 kcal · 100 kJ = 23.90057361 kcal
- Bookmark this page: Save this converter for instant access. It works offline once loaded — no internet needed.
Kilojoules to Kilocalories Conversion Table
| kJ | kcal |
|---|---|
| 0.01 kJ | 0.002390057361 kcal |
| 0.1 kJ | 0.02390057361 kcal |
| 0.5 kJ | 0.1195028681 kcal |
| 1 kJ | 0.2390057361 kcal |
| 2 kJ | 0.4780114723 kcal |
| 5 kJ | 1.195028681 kcal |
| 10 kJ | 2.390057361 kcal |
| 20 kJ | 4.780114723 kcal |
| 50 kJ | 11.95028681 kcal |
| 100 kJ | 23.90057361 kcal |
| 500 kJ | 119.5028681 kcal |
| 1000 kJ | 239.0057361 kcal |
All values in this table are mathematically exact per NIST SP 811.