Watt-hour to Kilojoule Converter
Convert watt-hours to kilojoules (Wh to kJ) instantly with this free online energy converter. Enter any value in the Watt-hour field and get the equivalent in Kilojoule immediately. This converter handles any quantity — from tiny fractions to large numbers — with full precision. No signup, no ads in the widget, and the conversion runs entirely in your browser for instant results.
The conversion factor is exact: 1 Wh = 3.6 kJ. To convert watt-hours to kilojoules, multiply your Watt-hour value by 3.6. For example, 10 Wh = 36 kJ. You can also reverse the calculation: 1 kJ = 0.2777777778 Wh.
Quick conversion table
| Watt-hour (Wh) | Kilojoule (kJ) |
|---|---|
| 1 Wh | 3.6 kJ |
| 5 Wh | 18 kJ |
| 10 Wh | 36 kJ |
| 25 Wh | 90 kJ |
| 50 Wh | 180 kJ |
| 100 Wh | 360 kJ |
Use the swap button to reverse the direction, or choose a different unit from the dropdown menus to convert within the energy category.
Formula
Watt-hour to Kilojoule conversion: 1 Wh = 3.6 kJ kilojoules = watt-hours × 3.6 1 kJ = 0.2777777778 Wh watt-hours = kilojoules × 0.2777777778
Example
Example: Convert 10 Wh to kJ: 10 Wh × 3.6 = 36 kJ So, 10 Wh is about 36 kJ. To convert back, multiply by 0.2777777778: 36 kJ × 0.2777777778 = 10 Wh.
How to Use
- Enter the value you want to convert in the Watt-hour field
- The result in Kilojoule appears instantly below
- Use the dropdown menus to change units if needed
- Click 'Swap Units' to reverse the conversion direction
- Copy the result or adjust the input for a new conversion
Frequently Asked Questions
How do I convert watt-hours to kilojoules?
Enter the value in Watt-hour (Wh) in the 'From' field. The equivalent in Kilojoule (kJ) appears instantly in the 'To' field. The converter uses precise conversion factors and updates in real time as you type.
What is the formula to convert Wh to kJ?
1 Wh = 3.6 kJ, so kilojoules = watt-hours × 3.6. To convert back, 1 kJ = 0.2777777778 Wh. The full formula and a worked example are shown on this page.
How many kilojoules are in one Watt-hour?
1 Wh = 3.6 kJ.
Is this Watt-hour to Kilojoule converter free?
Yes, completely free with no signup, no limits, and no ads in the converter widget. You can convert as many values as you need. The tool runs entirely in your browser, so your data never leaves your device.
Can I convert kilojoules back to watt-hours?
Yes. Click the 'Swap Units' button to reverse the direction. You can also use the dropdown menus to select any other energy unit for either field.
How accurate is the Wh to kJ conversion?
The converter uses high-precision conversion factors (up to 8 decimal places). Results are displayed with up to 6 decimal places, with trailing zeros removed for readability. For scientific or engineering work, always verify with official standards.