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Kilojoule [kJ] to Watt-hour [Wh] Converter

Quick Reference

1 Kilojoule (kJ) = 0.2777777778 Watt-hour (Wh)

1 Watt-hour (Wh) = 3.6 Kilojoule (kJ)

How to Convert Kilojoule to Watt-hour

1 kJ = 0.2777777777777778 Wh
1 Wh = 3.6 kJ

To convert Kilojoule to Watt-hour, divide the value by 3.6 (equivalently, multiply by 0.2777777778). To convert Watt-hour back to Kilojoule, multiply by 3.6.

Example: convert 10 kJ to Wh:
10 kJ = 10 x 0.2777777777777778 = 2.7777777777777777 Wh

↔ Convert Watt-hour to Kilojoule

Kilojoule

Definition: A kilojoule (symbol: kJ) is equal to 1000 joules. It's a unit of energy.

History/origin: Based on the joule, using the SI prefix 'kilo-' to denote a factor of one thousand.

Current use: Commonly used to express the energy content of food, fuels, and other substances when the joule would be impractically small. Also used in thermodynamics and other areas of physics and engineering.

Watt-hour

Definition: A watt-hour (symbol Wh) is a unit of energy equal to one watt of power sustained for one hour. It is commonly used to measure electrical energy consumption.

History/origin: The watt-hour is derived from the watt, the SI unit of power, and the hour, a unit of time. It was developed alongside the increasing use of electricity in the late 19th and early 20th centuries.

Current use: Watt-hours are commonly used to measure the energy capacity of batteries, the energy consumption of household appliances, and the amount of electricity generated or consumed by power plants and consumers.

Kilojoule to Watt-hour Conversion Table

Kilojoule [kJ]Watt-hour [Wh]
1 kJ0.2777777777777778 Wh
2 kJ0.5555555555555556 Wh
5 kJ1.3888888888888888 Wh
10 kJ2.7777777777777777 Wh
20 kJ5.555555555555555 Wh
50 kJ13.88888888888889 Wh
100 kJ27.77777777777778 Wh
200 kJ55.55555555555556 Wh
500 kJ138.88888888888889 Wh
1000 kJ277.77777777777777 Wh

Common pairs of Energy

Watt-hour

Watt-hour to Milliwatt-hourWatt-hour to Kilowatt-hourWatt-hour to Megawatt-hourWatt-hour to Gigawatt-hourWatt-hour to Joule

Milliwatt-hour

Milliwatt-hour to Watt-hourMilliwatt-hour to Kilowatt-hourMilliwatt-hour to Megawatt-hourMilliwatt-hour to Gigawatt-hourMilliwatt-hour to Joule

Kilowatt-hour

Kilowatt-hour to Watt-hourKilowatt-hour to Milliwatt-hourKilowatt-hour to Megawatt-hourKilowatt-hour to Gigawatt-hourKilowatt-hour to Joule

Megawatt-hour

Megawatt-hour to Watt-hourMegawatt-hour to Milliwatt-hourMegawatt-hour to Kilowatt-hourMegawatt-hour to Gigawatt-hourMegawatt-hour to Joule

Gigawatt-hour

Gigawatt-hour to Watt-hourGigawatt-hour to Milliwatt-hourGigawatt-hour to Kilowatt-hourGigawatt-hour to Megawatt-hourGigawatt-hour to Joule

Joule

Joule to Watt-hourJoule to Milliwatt-hourJoule to Kilowatt-hourJoule to Megawatt-hourJoule to Gigawatt-hour

Kilojoule

Kilojoule to Watt-hourKilojoule to Milliwatt-hourKilojoule to Kilowatt-hourKilojoule to Megawatt-hourKilojoule to Gigawatt-hour

Kilojoule [kJ] to Watt-hour [Wh] Converter

To convert Kilojoule to Watt-hour, enter your value in the kJ field above and the result in Wh will appear instantly. You can also use the conversion factor shown in the table on this page to calculate manually. The formula is always the same: multiply your kJ value by the fixed conversion ratio to get the equivalent in Wh.
Our Kilojoule to Watt-hour converter uses standardized conversion factors defined by international scientific and metrological organizations. All calculations are performed with full floating-point precision. You can also choose how many decimal places to display in the result, so you get exactly the level of detail you need.
Yes, absolutely. Simply swap the source and destination units in the converter β€” select Wh as your input unit and kJ as your output unit. The same precision and standardized conversion factor applies in both directions.
Converting between Kilojoule and Watt-hour comes up regularly in engineering, scientific research, construction, and everyday tasks that involve measurements from different unit systems. Our converter eliminates the risk of manual calculation errors and saves time whenever you need to switch between these two units.
Yes, the Kilojoule to Watt-hour converter is completely free. No account or registration is required, and there are no usage limits. It works on any device β€” smartphones, tablets, and desktop computers β€” directly in your browser.
Kilojoule and Watt-hour are both units used to measure the same physical quantity, but they belong to different measurement systems or represent different scales. The mathematical relationship between them is fixed and constant, which is what makes accurate conversion possible. Scroll up to see the exact conversion factor, formula, and a reference table for common values.