Skip to main content
ToolsHub

Convert Kilojoule to Watt Hour

Use this free converter to change kilojoules (kJ) into watt hours (Wh). Kilojoule and watt hour both measure energy. As a quick reference, 1 kJ equals 0.27777778 Wh, and 1 Wh equals 3.6 kJ.

Free · runs in your browser · no sign-up
Watt Hour (Wh)
0.27777778

1 kJ = 0.27777778 Wh

Energy conversion table

KilojouleWatt Hour
0.010.0027777778
0.10.027777778
0.50.13888889
10.27777778
20.55555556
30.83333333
51.3888889
102.7777778
205.5555556
256.9444444
5013.888889
10027.777778
1,000277.77778

How to convert Kilojoule to Watt Hour

Multiply the kilojoule value by 0.27777778 to get watt hours.

  1. Enter the number of kilojoules you want to convert.
  2. The converter instantly shows the equivalent value in watt hours.
  3. Worked example: 15 kJ × 0.27777778 = 4.1666667 Wh.
  4. Use the swap button to reverse the conversion (watt hour to kilojoule).

About these units

Kilojoule (kJ)

Definition
A kilojoule (kJ) is 1,000 joules, a practical size for food energy and mechanical work.
History
It is a metric multiple of the joule.
Current use
Kilojoules express food energy on nutrition labels in many countries.

Watt Hour (Wh)

Definition
A watt-hour (Wh) is the energy of one watt sustained for one hour, equal to 3,600 joules.
History
It arose with the electricity industry as a practical billing unit.
Current use
Watt-hours rate batteries and small energy stores.

Frequently asked questions

How many watt hours are in a kilojoule?

There are 0.27777778 Wh in 1 kJ. To convert, multiply the number of kilojoules by 0.27777778.

How do I convert kilojoules to watt hours?

Multiply the kilojoule value by 0.27777778 to get watt hours. For example, 10 kJ = 2.7777778 Wh.

Is this kilojoule-to-watt hour converter free?

Yes. This converter is completely free, runs entirely in your browser, and requires no sign-up. Your inputs never leave your device.

Convert Kilojoule to other energy units

Unit1 Kilojoule equals
Joule (J)1000 J
Calorie (cal)239.00574 cal
Kilocalorie (kcal)0.23900574 kcal
Watt Hour (Wh)0.27777778 Wh
Kilowatt Hour (kWh)0.00027777778 kWh
Electronvolt (eV)6.2415e+21 eV
British Thermal Unit (BTU)0.94781712 BTU
Foot-Pound (ft·lb)737.56215 ft·lb

More energy conversions

Browse all conversions