Online Energy Unit Converter
J / kJ / kcal / kWh / BTU
1 Kilowatt-hour = 3600000 Joule Click to copy
Common Conversions
About Energy Unit Conversion
The energy converter suits electricity bills, food calories, physics and engineering estimates, converting among joule, kilocalorie, kilowatt-hour and BTU. You can also use the Power Unit Converter to calculate watt, kilowatt and horsepower.
Common Formulas
- 1 kWh = 3600000 J
- 1 kcal = 4.184 kJ
- 1 cal = 4.184 J
- 1 BTU ≈ 1055.05585 J
Use Cases
- Electrical energy, food calories and physical energy calculations
- Energy/heat conversions between J, kJ, kcal, kWh and BTU
Tips
- The "calorie" in everyday food labels usually means kilocalorie (kcal); distinguish it from small calorie (cal).
FAQ
How many joules is 1 kWh?
1 kWh = 3600000 J = 3.6 MJ.
How many kilojoules is 1 kilocalorie?
1 kcal = 4.184 kJ.
What is the difference between calorie and kilocalorie?
1 kcal = 1000 cal. Kilocalorie (also "large calorie") is the most common energy unit on food nutrition labels.
What is BTU and how to convert it?
BTU is the British thermal unit, common in air conditioning and HVAC. 1 BTU ≈ 1055 J ≈ 0.252 kcal.
How to convert kcal and kJ?
1 kcal = 4.184 kJ. Divide the kJ on a food label by 4.184 to get kcal.