Battery and UPS runtime calculator
Enter the battery capacity (Ah or Wh), the load in watts and the inverter efficiency to get the runtime.
Result
A 100 Ah battery at 12 V (1200 Wh) powering a 100 W load at 90% efficiency lasts about 10.8 hours.
Example
Estimate how long a battery or UPS lasts under a given load in your browser. Values stay on your device.
A 100 Ah battery at 12 V (1200 Wh) powering a 100 W load at 90% efficiency lasts about 10.8 hours.
Processed locally in your browser.
Methodology
Runtime (h) = capacity (Wh) × efficiency / load (W). Convert Ah to Wh with Ah × voltage.
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