Ampere Hour and Watt Hour Calculator
Battery capacity is quoted in two ways, and this calculator converts freely between them. Ampere hours measure charge, watt hours measure energy, and the two are linked by voltage: watt hours equal amp hours times the battery voltage. Enter any two of amp hours, watt hours and voltage and the tool fills in the third, so you can compare a phone bank rated in milliamp hours against a power station rated in watt hours, or work out the true energy in a 12 volt lead acid pack. This matters when you are sizing storage for solar, planning airline carry on limits that are stated in watt hours, or matching a battery to a load. It also shows the milliamp hour value for small cells. Enter your figures and read every equivalent instantly. Everything runs locally in your browser, so it is fast and private.
How to use Ampere Hour and Watt Hour Calculator
- Enter the value you know, either amp hours or watt hours.
- Enter the battery or pack voltage.
- Read the converted energy capacity in the other unit.
- Use the result to compare packs on equal energy terms.
Frequently asked questions
How does it convert amp hours to watt hours?
It multiplies ampere hours by the battery voltage, since watt hours equal amp hours times volts, giving the true energy capacity.
Why is watt hours a fairer comparison than amp hours?
Amp hours ignore voltage, so two packs with the same Ah but different voltages store different energy; watt hours capture the full stored energy.
Can it work backwards from watt hours?
Yes, enter watt hours and voltage and it returns the ampere hours, so you can convert either direction for any pack or cell.
What is Ampere Hour and Watt Hour Calculator?
Battery capacity is quoted in two ways, and this calculator converts freely between them. Ampere hours measure charge, watt hours measure energy, and the two are linked by voltage: watt hours equal amp hours times the battery voltage.
Is Ampere Hour and Watt Hour Calculator free to use?
Yes. Ampere Hour and Watt Hour Calculator is completely free, with no sign-up and no usage limits.
Does Ampere Hour and Watt Hour Calculator work in a web browser?
Yes. Ampere Hour and Watt Hour Calculator runs in any modern web browser. There is nothing to download or install.
Is my data private with Ampere Hour and Watt Hour Calculator?
Yes. Ampere Hour and Watt Hour Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.
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