SI unit: joule (J)
Energy Converter
Energy measures the capacity to do work. The SI unit is joule (J), with calories, British thermal units (BTU), and kilowatt-hours in common use.
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Reference Table
View a complete conversion table for joules to calories.
View Reference Table →Frequently Asked Questions
How many joules in a calorie?
One thermochemical calorie equals exactly 4.184 joules.
What is the SI unit of energy?
The SI unit for energy is joule (J), defined as the work done by a force of one newton moving one meter.
How do I convert BTU to joules?
Multiply BTU by 1,055.06 to get joules. For example, 1,000 BTU equals approximately 1,055,060 J.