# Portable Power Station Runtime Calculator

Add up your devices to see the battery size you need, or how long a power station will run them.

- URL: https://toolstackhub.co.uk/tools/portable-power-station-runtime-calculator/
- Category: Calculators
- Price: free, no sign-up
- Privacy: runs in the browser; input is not uploaded
- Last updated: 2026-10-08

## About
List each device with its power in watts, the hours you use it, and how much of that time it is actually drawing power (a fridge cycles on and off). The calculator adds the watt-hours, checks the total running power against the power station's output limit, allows for inverter losses and a safety reserve, and tells you the capacity to look for. Or enter a power station's capacity and output to see its runtime.

## How to use
1. Paste or type your input into the box above.
2. Choose any options you need. Results update as you type.
3. Copy the result with the Copy button.

## FAQ
**How many watt-hours do I need?** Add up each device's watts multiplied by hours used (and by the share of time it is actually drawing power), then add 15 to 25% for inverter losses and a reserve.

**Can a power station run a kettle or heater?** Only if its output limit exceeds the appliance's wattage, and it will drain the battery fast. A 2,000 W kettle uses about 100 Wh to boil a litre in a few minutes.

**Is the Portable Power Station Runtime Calculator free?** Yes, with no sign-up or limits.