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Electrical Calculators

Battery Ah to Wh Calculator

Verified formula Updated Jun 2026 Private — runs on your device

Enter details
Ah
V
Verified formula Private

Energy

1,200.00

In kilowatt-hours
1.200

For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.

How to use the Battery Ah to Wh Calculator

The Battery Ah to Wh Calculator works out your energy, along with 1 related figure in an instant. Enter capacity and voltage and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.

  1. Enter the capacity.
  2. Enter the voltage.
  3. Read off your energy, together with in kilowatt-hours — the calculator updates automatically, with no button to press.

Formula

The Battery Ah to Wh Calculator uses the formula:

Energy = Capacity × Voltage

Worked example

For example, with capacity of 100 Ah and voltage of 12 V, the energy is 1,200.00.

Inputs used
Capacity 100 Ah
Voltage 12 V
Results
Energy 1,200.00
In kilowatt-hours 1.200

Results are estimates for educational use, not professional advice.

Frequently asked questions

Multiply amp-hours by voltage. A 100 Ah battery at 12 V stores 1,200 Wh, or 1.2 kWh.

Watt-hours let you compare batteries of different voltages on equal energy terms.

Use the battery's nominal voltage, such as 12 V for a lead-acid battery or 3.7 V per lithium cell.

Knowing watt-hours lets you match a battery to a load's energy use and estimate run time.

The Battery Ah to Wh Calculator uses the formula: Energy = Capacity × Voltage. For example, with capacity of 100 Ah and voltage of 12 V, the energy is 1,200.00.

Enter the capacity. Enter the voltage. Read off your energy, together with in kilowatt-hours — the calculator updates automatically, with no button to press.

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