Electric Charge Converter
Convert electric charge between coulombs, ampere-hours, milliampere-hours, elementary charges and CGS units.
Change the values and press Calculate to work out your own figures.
Enter an electric charge, choose its unit and the unit you want. The answer is exact until it is shown, and the same value appears in every other unit.
Show the working
- 1 mAh = 3.6 C
- 1000 × 3.6 = 3600 C
How to use it
Type an electric charge, choose the unit it is in and the unit you want, then press Calculate. You can type decimals, fractions such as 3/8, mixed numbers such as 1 1/2, very large or small numbers such as 2.5e6, and simple sums such as 2*3. Swap exchanges the two units.
The answer is worked out with exact fractions and only rounded for display, to 12 significant figures. Below it you get the same value in every other unit on the list, and Show the working gives the factor that was used.
Key definitions
1 C = 1 A × 1 s 1 Ah = 3,600 C; 1 mAh = 3.6 C e = 1.602176634 × 10⁻¹⁹ C
Battery capacity
Battery capacity in milliampere-hours is really an amount of charge: 1 mAh is 1 milliamp flowing for an hour, or 3.6 coulombs. It says nothing about voltage, so comparing batteries with different voltages needs watt-hours instead.
Questions
How many coulombs are in a milliampere-hour?
3.6 coulombs.
How many electrons make a coulomb?
About 6.241509 × 10¹⁸, the reciprocal of the elementary charge.
Formulas
result = (value × f(from) + o(from) − o(to)) ÷ f(to)
Sources
Limitations
- Only the units listed are supported here; other electric-charge units arrive with later M4 slices.