Kilowatt Hours to Watt Hours
Type a value in either box to convert between kilowatt hours and watt hours. The factor is 1000.
| Kilowatt Hours | Watt Hours |
|---|---|
| 1 kWh | 1000 Wh |
| 2 kWh | 2000 Wh |
| 3 kWh | 3000 Wh |
| 5 kWh | 5000 Wh |
| 10 kWh | 10000 Wh |
| 25 kWh | 25000 Wh |
| 50 kWh | 50000 Wh |
| 100 kWh | 100000 Wh |
How to use
- Enter a value in the Kilowatt Hours field.
- The Watt Hours figure appears immediately — no button to press.
- Typing in the Watt Hours field converts back to Kilowatt Hours the same way.
- Use the reference table for the values that come up most often.
Kilowatt Hours to Watt Hours formula
To convert kilowatt hours to watt hours, multiply by 1000.
Wh = kWh × 1000
Put another way, one kilowatt-hour is exactly 1,000 watt hours.
Why this factor: the kilowatt-hour and the watt-hour are both defined against the joule, so dividing one definition by the other gives 1000 directly. Both definitions are set out in full below.
To go the other way, divide by 1000 — or use the Watt Hours to Kilowatt Hours converter, which is the same calculation reversed.
Worked example
Take 500 kWh and multiply by the factor 1000: the result is 500000 Wh.
500 kWh × 1000 = 500000 Wh
The converter above does this for any value you type, in either direction.
What is a kilowatt-hour?
A kilowatt-hour is the standard billing unit for electricity — one kilowatt drawn for one hour.
Definition: Exactly 3.6 megajoules.
Where it is used: Electricity bills worldwide, solar generation figures, and electric vehicle battery capacity.
What is a watt-hour?
A watt-hour is the energy delivered by one watt of power sustained for one hour.
Definition: Exactly 3,600 joules.
Where it is used: Battery capacity for laptops, e-bikes and power tools, and small-scale energy metering.
Worth knowing: Airline lithium-battery limits are set in watt-hours, which is why laptop and power-bank capacities are labelled in Wh.
Kilowatt Hours vs Watt Hours
The kilowatt-hour and the watt-hour belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many watt hours are in a kilowatt-hour?
One kilowatt-hour equals 1000 watt hours.
What is the formula to convert kilowatt hours to watt hours?
Multiply the number of kilowatt hours by 1000. To reverse it, divide by 1000 instead.
How do I convert watt hours back to kilowatt hours?
Divide by 1000, which is the same as multiplying by 0.001.
How many watt hours are in 10 kilowatt hours?
10 kWh works out to 10000 Wh.
Is there anything to watch out for with watt hours?
Airline lithium-battery limits are set in watt-hours, which is why laptop and power-bank capacities are labelled in Wh.
How is the kilowatt-hour defined?
Exactly 3.6 megajoules.