Watt-hours to Kilojoules Converter
Enter the energy in watt-hours below to convert it to kilojoules.
Convert Watt-hours to Kilojoules
Enter a value in watt-hours (Wh) to convert to kilojoules (kJ).
Watt-hour to Kilojoule Conversion Table
Table showing various watt-hour measurements converted to kilojoules. Click any preset value or arrow to load it into the converter.
How to Convert Watt-hours to Kilojoules
To convert watt-hours to kilojoules, multiply the energy by the following conversion ratio: 3.6 kilojoules/watt-hour.
Since one watt-hour is equal to 3.6 kilojoules, you can use this simple formula to convert:
The energy in kilojoules is equal to the energy in watt-hours multiplied by 3.6.
For example, here's how to convert 5 watt-hours to kilojoules using the formula above.
How Many Kilojoules Are in a Watt-hour?
There are 3.6 kilojoules in a watt-hour, which is why we use this value in the formula above.
Our watt-hour to kilojoule calculator automatically converts your energy measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
Watt-hours and kilojoules are both units used to measure energy. Keep reading to learn more about each unit.
What Is a Watt-hour?
A watt-hour is a unit of energy equal to 3,600 joules (J), the base unit for energy. Equal to 3,600 Joules. [1]
The watt-hour is classified as a metric and SI-compatible unit of energy. Watt-hours can be abbreviated as Wh; for example, 1 watt-hour can be written as 1 Wh.
When working with watt-hours (Wh) in formulas or technical specifications, always verify whether your target system uses SI metric, US customary, or British imperial standards.
In practice, watt-hours (Wh) are widely used across large-scale industrial, bulk, and macro-level energy specifications within SI metric workflows, engineering documentation, and technical data sheets.
What Is a Kilojoule?
A kilojoule is a unit of energy equal to 1,000 joules (J), the base unit for energy. Equal to 1,000 Joules. [2]
The kilojoule is classified as a metric and SI-compatible unit of energy. Kilojoules can be abbreviated as kJ; for example, 1 kilojoule can be written as 1 kJ.
In the metric system, "kilo" is the standard SI prefix for thousands, or 10³. This makes the kilojoule (kJ) a convenient decimal multiple of the joule (J).
In practice, kilojoules (kJ) are widely used across large-scale industrial, bulk, and macro-level energy specifications within SI metric workflows, engineering documentation, and technical data sheets.
When converting energy between watt-hours (Wh) and kilojoules (kJ), keep full floating-point precision (1 Wh = 3.6 kJ; 1 kJ = 0.2777778 Wh) during intermediate calculations and round only the final kilojoule figure to match your instrument tolerance.
More Watt-hour & Kilojoule Conversions
Need to calculate in the opposite direction? Use our kilojoules to watt-hours calculator to switch your starting unit immediately. You can also explore related tools such as converting kilojoules to watt-hours, converting joules to kilojoules, or converting kilocalories to kilojoules.
Convert from Watt-hours
Frequently Asked Questions
References
- [1]NIST CODATA StandardNIST CODATA (CODATA Energy & Thermodynamic Constants)·Energy Metrology Standard — Watt-hours (Wh) to Kilojoules (kJ)
- [2]NIST SP 811 SpecificationNIST SP 811 (NIST SP 811 App. B.9 (Energy, Work & Heat))·Unit Specifications: Watt-hour (Wh) & Kilojoule (kJ)
- [3]BIPM ReferenceBIPM (Derived SI Unit: Joule (J))·Conversion Factors & Mathematical Basis (Wh to kJ)