Energy Converter Online - Joules, Wh and kWh
Convert energy values among joules, kilojoules, watt-hours and kilowatt-hours.
About this tool
Enter a number followed by j, kj, wh or kwh. The value is normalized to joules and returned in all four supported units.
How to use
- Enter the value in the format described by the tool.
- Run the conversion or calculation in your browser.
- Review and copy the generated result.
Features
- Joule and kilojoule output.
- Watt-hour and kilowatt-hour output.
- Supports negative and decimal numeric input.
Common use cases
- Compare battery energy ratings.
- Convert electricity calculations.
- Translate scientific and electrical energy units.
Common issues and tips
- Input must include a supported unit.
- This converts energy, not instantaneous power.
Privacy
Processing runs locally in your browser. Input is not uploaded to Tools12345.
Frequently asked questions
Which units are accepted?
j, kj, wh and kwh.
How many joules are in 1 Wh?
3600 joules.
Is kW the same as kWh?
No, kW is power and kWh is energy.