Enter a watt-hour energy figure and a voltage to convert it back into amp-hours.
How to Use the Watt-Hours to Amp-Hours Calculator
Enter a watt-hour energy figure and the system voltage it will run at. The equivalent amp-hour capacity appears below, recalculating with either field.
Going From a Spec Sheet Back to a Wiring Number
Inverters, solar controllers, and battery chargers are frequently specified in Wh, while the fuses, breakers, and wire gauges that connect to the battery bank are sized around amp-hours and current. This calculator bridges that gap: take the Wh figure off an inverter's storage spec or a manufacturer's energy rating, apply the actual battery voltage, and get the Ah number that the rest of the electrical design actually needs.
Amp-Hours = Watt-Hours ÷ VoltageA 1,200 Wh energy target at 12 V calls for 100 Ah of battery capacity; the same 1,200 Wh at 24 V only needs 50 Ah. Doubling the voltage halves the amp-hour requirement for identical stored energy — which is also why higher-voltage systems consistently need smaller, lighter battery banks to hit the same energy number.