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

Pick a power station, add what you run, and get an honest runtime estimate from real specs.

Power station

Type to filter by brand, model name, or slug. Choose from the list.

Devices

Nothing in your load yet

Pick a preset or custom below, then Add to load.

Inverter efficiency

DC → AC conversion loss. 85% is a safe default.

85%

Estimated runtime

Your estimate will show here

Add at least one device on the left. We combine its draw with your station's capacity and efficiency.

Using Jackery Explorer 300 Plus (288Wh, 300W output).

Jackery Explorer 300 Plus portable power station

When you're happy with your estimate, compare prices for Jackery Explorer 300 Plus.

Check price on Amazon

Affiliate link — helps support WattMatch

Compare models →

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.

Looking for specific products?

Browse Power Stations