Unit Converters · Science & Engineering Units
Energy Converter
Convert energy between joules and their multiples, calories and food kilocalories, watt-hours and kilowatt-hours (the 'units' on an electricity bill), British thermal units, therms, electronvolts, foot-pounds and ergs.
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Your result Live
1 Kilowatt-hour =
3.6 Megajoules
1 Kilowatt-hour = 3.6 Megajoules
- Joules
- 3,600,000
- Kilojoules
- 3,600
- Calories (cal)
- 860,420.6501
- Kilocalories (kcal, food Calories)
- 860.4206501
- Watt-hours
- 1,000
- British thermal units (BTU)
- 3,412.141633
- Therms (US)
- 0.03412956341
- Electronvolts
- 2.246943267 × 10²⁵
- Foot-pounds force
- 2,655,223.737
- Ergs
- 36,000,000,000,000
How this is calculated
Result = value × (joules per 'from' unit) ÷ (joules per 'to' unit)
- 1 kcal
- 4,184 J (thermochemical calorie); 1 kWh = 3.6 MJ; 1 BTU = 1,055.056 J
All energy units are fixed numbers of joules. A food Calorie on a label is a kilocalorie, 4.184 kJ. One kilowatt-hour — one 'unit' of electricity — is 3.6 million joules, about 860 kcal.
Assumptions & sources
- Calories are thermochemical (4.184 J); BTU is the International Table BTU.
- 1NIST Special Publication 811 — Guide for the Use of the International System of Units (conversion factors) — National Institute of Standards and Technology
- 2The International System of Units (SI Brochure, 9th edition) — BIPM
Calculator ID UNIT-ENERGY-001 · version 1.0.0
Common questions
How many kJ in a kcal?
4.184 kJ.
How many kcal is 1 kWh?
3,600,000 ÷ 4,184 ≈ 860 kcal.
What's an electronvolt?
The energy an electron gains across one volt: 1.602 × 10⁻¹⁹ J, used in physics and chemistry.