How to use it
- Enter power and choose W or kW.
- Enter usage time and choose hours per day or full 24-hour days.
- Optionally enter a day count for hours-per-day input, then calculate.
kWh Calculator
Convert power and operating time into estimated energy use in kWh and Wh.
Important: This calculator is for educational and estimation purposes only. It is not electrical safety, installation, engineering, or code-compliance advice. Always consult a qualified electrician or engineer for real-world electrical work.
About the kWh Calculator
This calculator converts a constant power level and time period into energy in watt-hours and kilowatt-hours.
How it works
Energy equals power in kW × operating hours. A full day represents 24 hours; hours-per-day can be multiplied by an optional number of days.
Example
A 1,000 W load used 8 hours per day for 30 days consumes an estimated 240 kWh.
Notes
The result assumes constant power. Cycling devices and variable loads require an average measured or estimated power value.