StationVerdict

Home / Runtime calculator

Power station runtime calculator

Choose a device or type its wattage. The list shows how long each power station runs it, and flags the ones that can't handle the load.

What are you powering?
W

Running several things at once? Add their watts together. Not sure? Check the appliance wattage chart.

Plugged into

Runtime

Longest runtime first

    Runtime = capacity (Wh) × efficiency ÷ draw (W). We assume 85% on AC and 92% on USB and 12 V. Battery age and cold weather lower real results.

    How the calculation works

    A power station's capacity is measured in watt-hours (Wh). Your device uses power in watts (W). Divide one by the other and you get hours, but not all of the stored energy reaches your device.

    Runtime (hours) = capacity (Wh) × efficiency ÷ device draw (W)

    Turning battery power into household AC power loses energy as heat in the inverter. We use 85% efficiency for AC outlets and 92% for USB and 12 V ports, which skip the inverter. Independent tests usually land between 80% and 90% on AC.

    The second limit is output. Each station has a maximum continuous output in watts. If your device draws more than that, the station shuts off no matter how full it is. Those rows show as over the limit. DC-only stations have no AC outlets, so they only appear when you choose USB / 12 V.

    Finding your device's real draw

    The wattage on a label is the peak. Fridges, CPAP heaters and space heaters cycle on and off, so their average is lower. For the most accurate number, plug the device into a plug-in power meter for a day and divide the kWh it shows by 24.

    Worked example

    A Jackery Explorer 1000 v2 holds 1,070 Wh. On a 40 W CPAP through the AC outlet: 1,070 × 0.85 ÷ 40 = 22.7 hours. Through a 12 V CPAP adapter it's 1,070 × 0.92 ÷ 40 = 24.6 hours.