Watt Ready

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What size power station do you need?

Pick a device below to see how long it will run. The math: capacity times 0.9, divided by your device's watts plus about 10W of inverter overhead.

Runtime calculator

Estimate. Assumes 90% usable energy plus about 10W that the power station's own inverter burns while its AC outlets are on. Check the label on your own device for real wattage.

Common device wattages

DeviceTypical drawNotes
Phone charging10 to 20WAbout 12 to 20Wh per full charge
WiFi router + modem10 to 20W
Laptop45 to 90W
CPAP10 to 25W averageHeated humidifier and hose raise it to 50 to 90W
Full-size fridge100 to 200W runningCycles on and off. Plan on 1 to 1.5 kWh per day
Microwave1,000 to 1,500WNeeds a 1,500W+ inverter
Space heater1,500WDrains 1 kWh in about 35 minutes. Not practical

Rules of thumb