kWh Cost Calculator
Energy in kilowatt-hours is (watts × hours) ÷ 1000. Multiply by your tariff. This ignores time-of-use rates, standing charges, and power factor.
Energy9 kWh
Cost$1.44
Formula
kWh = W × hours × days ÷ 1000. Cost = kWh × rate.
How to use this calculator
- Enter device watts.
- Enter daily hours and number of days.
- Enter your kWh price from a bill.
Examples
60 W lamp, 5 h/day, 30 days, $0.16/kWh
9 kWh, about $1.44.
FAQ
Where is the rate?+
On your electricity bill, often labeled supply or volumetric charge.
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