Convert Joules to Calories

The J-to-cal conversion appears often when working with energy data across different unit systems. Energy conversions connect food nutrition labels (calories), electricity bills (kWh), and scientific measurements in joules or BTU.

To convert, multiply the joules value by 0.239006. Written as an equation: cal = J × 0.239006.

One joules equals approximately 0.239006 cal. This means you can multiply any J value by 0.239006 to get the equivalent in cal.

Worked example: 10 J = 2.390057 cal. Enter your own value in the converter above for instant results.

Common mistake: Food calories on nutrition labels are actually kilocalories (kcal), which confuses many people when comparing to joules or watt-hours.

Bookmark this page for quick J to cal conversions, or use the swap button to reverse the direction and convert cal back to J.