Convert Coulombs to Milliampere-hours
Convert Coulombs (C) to Milliampere-hours (mAh) instantly and accurately.
Conversion Formula
mAh = C × 0.2777777778
About Coulombs
The coulomb (C) is the SI derived unit of electric charge, equal to the charge transported by a current of 1 A in 1 s. In the 2019 SI revision it is fixed exactly via the elementary charge: 1 C = 1 / (1.602 176 634 × 10⁻¹⁹) e ≈ 6.241 × 10¹⁸ e. Practical benchmarks: a 1 Ah battery stores 3 600 C; a lightning bolt transfers 1-20 C.
About Milliampere-hours
The milliampere-hour (mAh) equals exactly 3.6 C and is the universal capacity unit for portable-electronics batteries. Smartphone batteries range from 3 000-5 000 mAh; AA alkaline cells deliver ≈2 500 mAh; small lithium coin cells for RTC modules are rated 35-225 mAh. 1 mAh = 3.6 C = 10⁻³ Ah.
Quick Reference Table
| Coulombs (C) | Milliampere-hours (mAh) |
|---|---|
| 1 C | 0.277778 mAh |
| 2 C | 0.555556 mAh |
| 5 C | 1.38889 mAh |
| 10 C | 2.77778 mAh |
| 25 C | 6.94444 mAh |
| 50 C | 13.8889 mAh |
| 100 C | 27.7778 mAh |