100 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 100 Ah battery at 12 V provides 1.200 Wh of total energy—ideal for backing up an off-grid cabin or running a 200W appliance for roughly 6 hours. If configured in a 24 V system, that 100 Ah bank delivers 2.400 Wh, while a 48 V system yields an impressive 4.800 Wh.

Battery Capacity	Energy at 12V	Energy at 24V	Energy at 48V
100 Ah	1.200 Wh	2.400 Wh	4.800 Wh

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

Quick answer

100 Ah is 1,200 Wh at 12 V DC. At other common voltages — 24 V: 2,400 Wh, 48 V: 4,800 Wh. Use the calculator below for any voltage or circuit type.

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

In practice: the 100 Ah van and RV standard

A 100 Ah battery at 12.8 V stores 1,280 Wh, the default building block for van conversions and RV house banks. Realistically that runs a compressor fridge, LED lighting, a water pump and device charging for about a day and a half with no sun. Work out your daily watt-hour consumption first and divide by the pack's watt-hours — sizing from amp-hours alone hides the voltage term and leads people astray.

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.