UPS / Inverter Battery Runtime

Calculate how long a battery can power a load through a UPS or inverter, free online.

Battery capacity (Ah)

Battery voltage (V)

Number of batteries (same voltage, in parallel)

Usable depth of discharge (%)

Inverter efficiency (%)

Load (watts)

Acerca de esta calculadora

Usable energy = battery voltage × amp-hours × depth of discharge (DoD) × inverter efficiency. Runtime = usable Wh ÷ load W. Lead-acid batteries should only be discharged to 50%; lithium (LiFePO₄) to 80–90%.