Electric charge converter
Convert between coulombs and mAh, the battery unit, and see how many electrons that actually is.
That's 240× as much charge as a lightning strike, while a phone battery is 5× more. That is about 2.247×10²² electrons.
What it means
How much charge is that?
Charge is not energy: to get watt-hours from mAh you also need the voltage.
Every unit
Your charge in every unit
Learn
Three things worth knowing
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1 mAh = 3.6 coulombs
An hour is 3,600 seconds, and a milliamp is a thousandth of an amp, so the two factors leave 3.6.
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Counting the electron
Since 2019 the coulomb is defined by fixing the electron’s charge at exactly 1.602176634×10⁻¹⁹ C, making charge a matter of counting electrons.
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Charge is not capacity in watt-hours
Two batteries with the same mAh hold different energy if their voltages differ. Charge times voltage gives energy.
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Background
About charge units
The SI unit is the coulomb: one amp flowing for one second. Batteries use milliamp-hours, which is the same thing on a friendlier scale, since 1 mAh is 3.6 coulombs.