Watt Hour Calculator
Calculate energy consumption in watt-hours (Wh) and kilowatt-hours (kWh) from device wattage and usage time.
watts
hours
$/kWh
Energy Consumption
—Wh
kWh—
Cost—
Monthly (30 days)—
Watt Hour Formula
Wh = Watts × Hours. kWh = Wh ÷ 1000. Average US electricity rate is $0.12/kWh.