FORMULA
How to convert
J = kWh × 3600000Example: 10 kWh = 36000000 J.
KWH → J
Kilowatt-Hours to Joules
Convert kilowatt-hours to joules with an exact, deterministic calculation.
LIVE CONVERSIONDECIMAL ENGINE EXACT_
1 kWh = 3600000 J
MULTI-CONVERT
QUICK ANSWER
1 Kilowatt-hour
3600000 J
REFERENCE TABLE
Kilowatt-hour to Joule
| kilowatt-hours | joules |
|---|---|
| 1 kWh | 3600000 J |
| 5 kWh | 18000000 J |
| 10 kWh | 36000000 J |
| 25 kWh | 90000000 J |
| 50 kWh | 180000000 J |
| 100 kWh | 360000000 J |
ABOUT THIS CONVERSION
Convert kilowatt-hours to joules
A kilowatt-hour measures energy delivered by one kilowatt for one hour. Since one watt equals one joule per second and one hour has 3,600 seconds, one kilowatt-hour equals exactly 3.6 million joules.
Real-world example
An energy amount of 1 kWh is 3600000 J. Electricity bills normally retain kWh because joules would create very large numbers for household use.
Rounding and precision
Billing and nutrition should follow the precision of the original label. Scientific work should preserve significant figures. Small electronvolt values converted to joules may be clearer in scientific notation.
Regional context
Food labels may write 'Calories' with a capital C to mean kilocalories. Kilojoules are prominent on labels in many countries, while food Calories are common in the United States. BTU conventions can vary slightly; this site states its stored factor.
Common mistake
Do not confuse kWh with kW. A 2 kW appliance uses 1 kWh in half an hour only if it runs continuously at that power.
Editorial method
Definitions and sources are listed below. Calculations retain more precision than the default display and round only for presentation.
USEFUL ANSWERS
kWh to J FAQs
Is a kilowatt-hour a unit of power?
No. It is energy; kilowatt is power, while multiplying power by time gives energy.
Why is 1 kWh 3.6 MJ?
One kilowatt is 1,000 joules per second, and an hour is 3,600 seconds, producing 3,600,000 joules.
How do I convert kilowatt-hours to joules?
Enter the kWh value in the calculator. It applies the stored factor and offset definitions and returns the equivalent in J; the formula and common-value table are shown on this page.
Is the kWh to J conversion exact?
Defined measurement relationships are calculated with decimal arithmetic from stored standards. The displayed answer may be rounded for readability. Currency results instead depend on the dated reference rate shown.
FROM UNIT
Kilowatt-hour
The kilowatt-hour (kWh) is an energy unit equal to exactly 3.6 megajoules. It measures energy, work, or heat rather than the rate of energy transfer.
NIST Guide to the SI, SP 811 ↗Definition verified 14 August 2026TO UNIT
Joule
The joule (J) is the SI unit of energy, equal to the work done by one newton through one meter. It measures energy, work, or heat rather than the rate of energy transfer.
NIST Guide to the SI, SP 811 ↗Definition verified 14 August 2026Content reviewed by Akhil Saroop · 16 August 2026 · Report an error on this page