Calories (cal) to Watt-Hours (Wh) Converter
Enter a value to instantly convert between energy units.
1 Calorie (thermochemical) = 0.0012 Watt-Hour
Key Formulas
Kilocalorie → Kilojoule
kJ = kcal × 4.184Kilojoule → Kilocalorie
kcal = kJ × 0.239006Kilowatt-Hour → Joule
J = kWh × 3600000Joule → Kilowatt-Hour
kWh = J × 2.77778e-7Formula
Wh = cal ÷ 859.845One thermochemical calorie equals about 0.001162 watt-hours — since 1 cal = 4.184 J and 1 Wh = 3600 J, the conversion is 1 cal = 4.184/3600 = 0.001162 Wh. This is useful when comparing food energy to electrical energy costs.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A nutrition student calculating that 859.8 cal equals exactly 1 Wh for the textbook.
859.845 cal = 1 Wh
A food scientist analyzing 1000 cal of energy content converts to 1.163 Wh for comparison.
1000 cal = 1.163 Wh
A dietician calculating 100 cal from a snack reports 0.1163 Wh equivalent for the patient.
100 cal = 0.1163 Wh
A fitness tracker showing 5000 cal burned converts to 5.814 Wh for the energy display.
5000 cal = 5.814 Wh