Power Station Calculators
The two questions readers ask most — how many nights, and will it start — answered for your own numbers rather than a generic example.
Both calculators run the arithmetic published on how we research: the 0.85 inverter factor applied once, on the capacity side; surge ratings taken from manufacturer specs; nothing measured on a bench, because we don't claim to have one.
CPAP Runtime Calculator
Nights per charge for your CPAP on any station we track.
Enter machine wattage, humidifier setting, and sleep length. Usable capacity is rated Wh × 0.85 for the inverter; 12V DC input skips that loss. Nights round down to the half-night.
Open the cpap runtime calculatorRead the method: Best power stations for CPAP · The runtime comparison table · 12V DC vs the AC inverter
Appliance Surge Sizer
Which stations clear the startup surge of a refrigerator, chest freezer, sump pump, window AC, or saw.
Pick an appliance for a published typical surge range, or enter the compressor LRA from the nameplate (LRA × 120V). Every station is checked against its manufacturer surge and output ratings.
Open the appliance surge sizerRead the method: Surge watts vs running watts · Port wattage limits
Missing a calculator you'd use — solar recharge time, or “what will 1000W run”? Tell us on the contact page. The next one gets built from the most-asked question.