ToolsRuntime Calculator

How long will your battery last?

Select a power station, add the devices you want to run, and get an estimated runtime based on real capacity and inverter efficiency. Adjust the efficiency slider if you want a more conservative or optimistic estimate.

Runtime Calculator

Select a power station and add devices to estimate how long your battery will last.

Devices

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85%

Accounts for energy lost during DC→AC conversion. Default 85% is a safe estimate.

Estimated Runtime

Add devices on the left to see your runtime estimate.

Selected: Jackery Explorer 300 Plus

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How this works

Real capacity data

Specs come directly from the manufacturer. We use the rated watt-hours, which is what's actually in the battery.

Inverter efficiency

When a battery converts DC to AC power, some energy is lost. Default 85% is a reasonable real-world estimate. LiFePO4 batteries often hit 90%+.

The formula

(Capacity × Efficiency) ÷ Total Watts = Hours. Simple, honest, no padding.

Keep in mind

Device wattage can vary. A mini fridge draws 60W when the compressor runs, but cycles off and on — average draw over time is much lower. For intermittent devices, consider cutting their wattage in half for a more realistic estimate. Temperature, battery age, and load mix also affect real-world runtime.

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