How do I convert kilojoules back to calories?

Use the reverse converter: 1 kilojoule equals 239.006 cal.

Is this converter accurate?

Yes. It uses the exact SI/NIST definitions of each unit and shows up to 6 significant digits.

To convert calories to kilojoules, multiply the value by 0.004184.

kJ = cal × 0.004184

40 cal × 0.004184 = 0.1674 kJ

Calorie (cal): The thermochemical calorie is exactly 4.184 joules, historically the heat to warm one gram of water by 1 °C.
Kilojoule (kJ): 1,000 joules; used for food energy in Australia, New Zealand and much of Europe.

How do I convert calories to kilojoules?: To convert calories to kilojoules, multiply the value by 0.004184.
How many kilojoules are in 1 calorie?: 1 calorie equals 0.004184 kJ.
How many kilojoules are in 10 calories?: 10 cal equals 0.04184 kJ.
How do I convert kilojoules back to calories?: Use the reverse converter: 1 kilojoule equals 239.006 cal.
Is this converter accurate?: Yes. It uses the exact SI/NIST definitions of each unit and shows up to 6 significant digits.