Watt-Hours (Wh) to Joules (J) Converter
Enter a value to instantly convert between energy units.
1 Watt-Hour = 3600 Joule
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
J = Wh × 3600A watt-hour is the energy delivered by one watt of power for one hour — exactly 3600 joules since power is energy per time. Watt-hours are standard for electricity consumption (your electric bill is in kWh), while joules are the SI base unit. Converting to joules means multiplying by 3600.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A homeowner checking their electricity bill noting that 1 kWh equals 3,600,000 J for the conversion.
1 Wh = 3600 J
An engineer calculating 50 Wh of battery capacity records 180,000 J in the design document.
50 Wh = 180000 J
A technician measuring 0.5 Wh from a small solar cell writes 1800 J in the log.
0.5 Wh = 1800 J
A data center calculating 100 Wh of UPS backup capacity needs 360,000 J for the specification sheet.
100 Wh = 360000 J