Energy Use Calculator
Use this kWh calculator when you need energy use before applying a utility rate or cost estimate.
Result
- Total connected power
- W
- Daily energy
- kWh/day
- Total energy
- kWh
- Average power over full day
- kW
Calculation details
- Calculation basis
- Boundary
Recent results
Formulas
- Total watts = watts per item x quantity
- Daily energy kWh = total watts / 1000 x hours per day
- Total energy kWh = daily energy kWh x days
Use this calculator
Estimate daily and total kWh from load watts, quantity, runtime, and days.
Read the result
Review the calculated values with their displayed units and assumptions. The result is a planning aid for the stated inputs, not a final equipment or installation decision.
Check before final work
This is a simple energy-use estimate. Real use can change with duty cycle, controls, standby power, weather, occupant behavior, and measurement accuracy.
FAQs
Is kWh the same as kW?
No. kW is power at an instant. kWh is energy over time, so runtime matters.
Can I use this before estimating cost?
Yes. Use the kWh result here, then apply a rate in the Electricity Cost Calculator if you need a cost estimate.