What this converter does
This converter turns watt-hours into ampere-hours and back. Because energy is charge times voltage, enter the battery voltage — 12 V is the default for lead-acid and solar banks. Type a value and read the result as you type.
Solar and off-grid batteries are often specified both ways, so a consistent conversion at the right voltage matters.
The units it covers
Energy (Wh) and charge (Ah) are linked by the battery voltage — energy is charge times voltage.
View all units & their values
| Unit | Symbol | Value | Mainly used |
|---|---|---|---|
| Watt-hour | Wh | energy | Battery energy capacity |
| Ampere-hour | Ah | charge | Battery charge rating |
| Voltage | V | input | Nominal battery voltage |
The formula
Energy equals charge times voltage, so watt-hours and ampere-hours relate through the voltage:
Wh = Ah × VWhere:
- Wh = energy in watt-hours
- Ah = charge in ampere-hours
- V = nominal battery voltage
Worked example
Convert 600 Wh at 12 V to Ah.
Ah = Wh ÷ V600 ÷ 12 = 50 AhSo a 600 Wh battery at 12 V is a 50 Ah battery.
The units in this example
A unit of energy — the true stored capacity of a battery, independent of voltage.
- 1 Wh = 0.001 kWh
- Wh = Ah × V
- 600 Wh @12V = 50 Ah
- 1,000 Wh = 1 kWh
A unit of electric charge — the common capacity rating for lead-acid, solar and EV cells.
- 1 Ah = 1,000 mAh
- Ah = Wh ÷ V
- 100 Ah @12V = 1,200 Wh
- Ah × V = Wh