How to convert coulombs to milliampere-hours
mAh = C × 0.2777777778Because one milliampere-hour equals 3.6 coulombs, you can also divide: mAh = C ÷ 3.6.
A coulomb is smaller than a milliampere-hour: it takes 3.6 coulombs to make one milliampere-hour.
Worked examples
- 1 coulomb1 C × 0.2777777778 = 0.2777777778 mAh
- 5 coulombs5 C × 0.2777777778 = 1.388888889 mAh
- 10 coulombs10 C × 0.2777777778 = 2.777777778 mAh
- 20 coulombs20 C × 0.2777777778 = 5.555555556 mAh
- 100 coulombs100 C × 0.2777777778 = 27.77777778 mAh
Coulombs to milliampere-hours conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| Coulombs (C) | Milliampere-hours (mAh) |
|---|---|
| 0.1 C | 0.027777778 mAh |
| 0.25 C | 0.069444444 mAh |
| 0.5 C | 0.13888889 mAh |
| 1 C | 0.27777778 mAh |
| 2 C | 0.55555556 mAh |
| 3 C | 0.83333333 mAh |
| 4 C | 1.1111111 mAh |
| 5 C | 1.3888889 mAh |
| 6 C | 1.6666667 mAh |
| 7 C | 1.9444444 mAh |
| 8 C | 2.2222222 mAh |
| 9 C | 2.5 mAh |
| 10 C | 2.7777778 mAh |
| Coulombs (C) | Milliampere-hours (mAh) |
|---|---|
| 12 C | 3.3333333 mAh |
| 15 C | 4.1666667 mAh |
| 20 C | 5.5555556 mAh |
| 25 C | 6.9444444 mAh |
| 30 C | 8.3333333 mAh |
| 40 C | 11.111111 mAh |
| 50 C | 13.888889 mAh |
| 75 C | 20.833333 mAh |
| 100 C | 27.777778 mAh |
| 250 C | 69.444444 mAh |
| 500 C | 138.88889 mAh |
| 1,000 C | 277.77778 mAh |
About the units
Coulomb (C)
The SI unit of charge: one ampere for one second.
Milliampere-hour (mAh)
3.6 coulombs. Phone and power-bank batteries are rated in mAh.
Frequently asked questions
How many milliampere-hours are in one coulomb?
There are 0.2777777778 milliampere-hours in one coulomb, and this value is exact by definition.
How do I convert coulombs to milliampere-hours?
Multiply the number of coulombs by 0.2777777778. For example, 10 C × 0.2777777778 = 2.777777778 mAh.
How many coulombs are in one milliampere-hour?
One milliampere-hour equals 3.6 coulombs. That is the reverse factor, 1 ÷ 0.2777777778.
What is 10 coulombs in milliampere-hours?
10 C = 2.777777778 mAh.
Is this C to mAh converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.