How Do I Convert Between mAh and Ah?

Milliampere-hour and ampere-hour measure the same thing, battery capacity, on different scales. One ampere-hour equals one thousand milliampere-hours. To convert, divide mAh by one thousand to get Ah, or multiply Ah by one thousand to get mAh. A 2000 mAh cell is therefore a 2 Ah cell.

Why Voltage Matters for Real Energy

Capacity alone does not tell you how much energy a pack stores. Multiply capacity in Ah by nominal voltage to get watt-hours: Wh equals Ah times V. Two 2000 mAh cells at different voltages deliver different runtime, so comparing watt-hours rather than mAh gives a fairer picture.

Reading Custom Pack Ratings

This is especially important when comparing custom packs, where cells may be wired in series to raise voltage while keeping the same capacity rating. Always check the nominal voltage printed on the cell before comparing ratings across products. For example, a 3.85 V cell rated at 3000 mAh stores about 11.55 Wh, while the same 3000 mAh at 3.7 V stores about 11.1 Wh. Series connections raise voltage and therefore watt-hours, but they do not change the mAh rating of the pack, so checking both prevents apples-to-oranges comparisons.