Inverter & Battery Calculator

power factor {{ cat.pf.toFixed(1) }}

{{ item.watts }}W

Add your own — pedestal fan, monitor, anything

Not sure which category? Anything with a motor or compressor → "Fan / motor". Chargers, TVs, routers → "Electronics". Bulbs and tubelights → "Lighting".

Total load

{{ realWatts }}W

Inverter capacity needed

{{ recommendedVA }}VA

—

≈ {{ invCapacityW }}W usable, incl. surge margin

how this is worked out

Each appliance's watts is divided by its power factor to get VA (motors and electronics need more supply than they use as work). Raw need here is {{ rawVA }}VA — we add ~15% headroom for fan startup surge, then round up to a standard inverter size.

How long should power last?

{{ hours }}h

Battery capacity needed

{{ battery.banks > 1 ? battery.banks + ' × ' : '' }}{{ battery.ah }}Ah

—

gives ~{{ battery.actualHours }}h at this load

This needs {{ battery.banks }} batteries in parallel. Confirm your inverter explicitly supports multiple batteries before buying — most home inverters only take one.

Inverter & battery calculator

{{ cat.label }}

Add your own — pedestal fan, monitor, anything