Size from the load
Start with what must stay on, not a product name or sale price.
Home outage planning
Know what your backup battery needs to handle.
Build an essential-load plan, account for compressor surge and real usage, then size the battery before comparing brands.
Build your outage plan Refrigerator duty-cycle planning Communications and lighting loads Editable safety and efficiency assumptions
Free planning tool
Portable power station sizing calculator
Add the devices you need during an outage. Use the labels on your own appliances when possible; the presets are planning defaults.
Step 1
Build your essential load
DeviceRunning WSurge WHours/dayDuty %
Add a common device
How we work
A recommendation should be auditable.
A battery's headline capacity does not tell you what it can run. Our process starts with energy use, then checks continuous output, startup surge, reserve, conversion loss, and recharge constraints.
Read the full methodologyShow the assumptions
Efficiency, reserve, duty cycle, and surge headroom stay visible and editable.
Separate facts from claims
Published specifications are labeled. Real-world performance needs sourced testing.
No sponsored result inside the calculator.
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