Tool
Home Backup Watt-Hour Calculator
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Estimate how many watt-hours (Wh) of battery capacity you may need for a short outage or camping day. Enter each device’s running watts and hours of use. This is planning math — not a lab test of your fridge or power station. Always check device nameplates and your fridge’s EnergyGuide label.
Device loads
Per device: Wh = watts × hours × duty cycle. Default duty cycle is 1.0. For cycling fridges, prefer EnergyGuide daily Wh (use the preset) over guessing duty cycle.
| Device | Running W | Hours | Surge W | Duty |
|---|
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