Kilocalories to Kilojoules

One kilocalorie equals 4.184 kilojoules.

Kilojoules = kilocalories × 4.184

Energy Converter

From

Common Conversions

Energy Examples

Household Energy

• Average home daily use: ~30 kWh
• LED bulb (10W, 1 hour): 36 kJ
• Microwave (1000W, 2 min): 120 kJ
• Electric car (100 miles): ~30 kWh

Food Energy

• Apple: ~350 kJ (80 kcal)
• Slice of bread: ~315 kJ (75 kcal)
• Can of soda: ~590 kJ (140 kcal)
• Daily intake: ~8400 kJ (2000 kcal)

Energy Unit Reference

Scientific Units

• Joule (J): SI base unit of energy
• Calorie (cal): Energy to heat 1g water by 1°C
• Electron Volt (eV): Atomic scale energy
• Erg: CGS unit (very small)

Practical Units

• kWh: Electrical energy billing
• BTU: Heating/cooling systems
• Therm: Natural gas billing
• kcal: Food energy (Calories)

Kilocalories to Kilojoules Conversion Table

kcal	kJ
1	4.184
5	20.92
10	41.84
25	104.6
50	209.2
100	418.4
150	627.6
200	836.8
250	1046
300	1255.2
400	1673.6
500	2092
750	3138
1000	4184
2000	8368

About This Conversion

Kilocalories to kilojoules multiplies by 4.184, and is the conversion between the two units food labels use. The kilocalorie is what Americans call a Calorie; the kilojoule is what appears first on labels in Australia, New Zealand and much of Europe.

The daily reference figures make the scale clear: 2,000 kcal is 8,368 kJ, and the 8,700 kJ printed on Australian labels is 2,079 kcal. The two systems describe the same energy, so a product is not more or less caloric for being labelled in kilojoules.