Not sure how big a power station you need? Pick the appliances you want to run, set how long you need power, and this free calculator works out the watt-hours (Wh) and output watts you need, then shows the portable power stations we have reviewed that actually fit.
Pick what you want to power
Typical wattages are pre-filled. Check your device label and edit the numbers for a more accurate result. For fridges and freezers, “hours” means compressor run time, not hours plugged in.
| Appliance | Watts | Hours/day | Qty | Wh/day |
|---|
How long do you need power?
Recharging with solar? (optional)
Your result
Power stations that fit
Select at least one appliance to see matching power stations.
Estimates only: real runtime depends on temperature, battery age and how often compressors cycle. Some links are affiliate links; if you buy through them we may earn a commission at no extra cost to you. Learn more.
How the calculator works
Daily energy (Wh) is each appliance’s watts × hours of use per day × quantity. For fridges and freezers, use compressor run time (usually 6 to 10 hours a day), not the 24 hours they stay plugged in.
Recommended capacity multiplies your daily energy by the number of days, then divides by 0.85 to account for inverter losses and the part of the battery you cannot use, and adds your safety headroom. Cold weather and an aging battery both cut real capacity, so 20% headroom is a sensible default.
Continuous output (W) is what the inverter must deliver at once. Startup surge matters for anything with a motor or compressor (fridges, pumps, air conditioners), which can briefly draw two to three times their running watts. Most power stations handle roughly double their rated output for a few seconds.