300 Ah to Wh

Q: How do I convert Ah to Wh?

Multiply the amp-hours by the battery voltage: Wh = Ah × V. For example, a 100 Ah battery at 12 V stores 100 × 12 = 1,200 Wh. Use the nominal (rated) voltage of the battery.

Q: How many watt-hours is a 100Ah 12V battery?

A 100 Ah battery at 12 V holds 100 × 12 = 1,200 Wh, which is 1.2 kWh. At 24 V the same 100 Ah would hold 2,400 Wh, and at 48 V it would hold 4,800 Wh.

Q: Which voltage should I use for the conversion?

Use the battery's nominal voltage — for example 3.7 V for a Li-ion cell, 12 V for a lead-acid battery, or 48 V for a solar storage bank. The nominal voltage represents the average voltage during discharge.

Q: What is the difference between Ah and Wh?

Amp-hours (Ah) measure charge capacity and ignore voltage, while watt-hours (Wh) measure energy and include voltage. Wh is the fairer way to compare batteries of different voltages, since Wh = Ah × V.

Reviewed by the ElectricalConverters editorial team Last updated July 2026 Estimates only — how we check

Enter amp-hours and battery voltage below — the watt-hours update instantly.

A high-capacity 300 Ah battery at 12 V provides 3.600 Wh of total energy—ideal for backing up an off-grid cabin or running a 200W appliance for roughly 18 hours. If configured in a 24 V system, that 300 Ah bank delivers 7.200 Wh, while a 48 V system yields an impressive 14.400 Wh.

Battery Capacity	Energy at 12V	Energy at 24V	Energy at 48V
300 Ah	3.600 Wh	7.200 Wh	14.400 Wh

50Ah 100Ah 150Ah 200Ah 250Ah 300Ah 400Ah

Amp-hours (Ah)

Voltage (V)

Common battery voltages — click to fill

RESULT — ENERGY

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Formula: Wh = Ah × V

How do you convert Ah to Wh?

Multiply amp-hours by voltage: Wh = Ah × V. A 100 Ah battery at 12 V stores 100 × 12 = 1,200 Wh (1.2 kWh). Always use the battery's nominal voltage — a 100 Ah bank at 48 V holds four times the energy of the same 100 Ah at 12 V, because watt-hours scale directly with voltage.

Ah to Wh Formula

Wh = Ah × V

Amp-hours measure electric charge; watt-hours measure energy. Since energy = charge × voltage, multiplying capacity in Ah by the battery voltage gives the stored energy in Wh. This is why two batteries with the same Ah rating hold different energy if their voltages differ.

Ah to Wh at Common Battery Voltages

Capacity	at 3.7 V	at 12 V	at 48 V
2 Ah	7.4 Wh	24 Wh	96 Wh
5 Ah	18.5 Wh	60 Wh	240 Wh
10 Ah	37 Wh	120 Wh	480 Wh
50 Ah	185 Wh	600 Wh	2,400 Wh
100 Ah	370 Wh	1,200 Wh	4,800 Wh
200 Ah	740 Wh	2,400 Wh	9,600 Wh

Frequently Asked Questions

How do I convert Ah to Wh?

Multiply amp-hours by voltage: Wh = Ah × V. A 100 Ah battery at 12 V stores 100 × 12 = 1,200 Wh. Always use the battery's nominal voltage.

How many watt-hours is a 100Ah 12V battery?

100 Ah × 12 V = 1,200 Wh (1.2 kWh). At 24 V it would be 2,400 Wh; at 48 V, 4,800 Wh — the energy scales with voltage.

Which voltage should I use for the conversion?

Use the nominal voltage — 3.7 V for a Li-ion cell, 12 V for lead-acid, 48 V for a solar bank. It represents the average voltage across a discharge, which the preset buttons above fill for you.

What is the difference between Ah and Wh?

Ah measures charge and ignores voltage; Wh measures energy and includes it. Because Wh = Ah × V, watt-hours are the fairer way to compare batteries of different voltages.