Electric charge converter
Type a charge, choose the units, and see the result plus the same charge in every common unit. It also turns battery capacity in mAh or Ah into coulombs.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Type a number. A dot or a comma works as the decimal separator.
- Choose the unit you have and the unit you need. The ⇄ button swaps them.
- The table below shows the same value in all common units at once.
Conversion factors
Every unit is converted through the coulomb (C).
| Unit |
Value |
| 1 milliamp-hour (mAh) |
3.6 C |
| 1 amp-hour (Ah) |
3,600 C |
| 1 faraday |
96,485.33212 C |
| 1 elementary charge |
1.602176634 × 10⁻¹⁹ C |
| 1 abcoulomb |
10 C |
Worked example
A 5,000 mAh power bank holds 5,000 × 3.6 = 18,000 C, which is 5 Ah. At 3.7 V that is 5 × 3.7 = 18.5 Wh of energy.
Quick reference
- 1 mAh = 3.6 C and 1 Ah = 3,600 C
- mAh and Ah measure charge; watt-hours (Wh) measure energy
- 1 C = 1 A·s
Frequently asked questions
How many coulombs are in an amp-hour?
Exactly 3,600. One amp-hour is one ampere flowing for 3,600 seconds, and one ampere is one coulomb per second.
How do I convert mAh to coulombs?
Multiply by 3.6. A 3,000 mAh phone battery stores 3,000 × 3.6 = 10,800 C. This is charge, not energy; to get energy you also need the voltage.
What is the faraday?
The charge of one mole of elementary charges: 96,485.33212 C/mol, equal to the Avogadro constant times the elementary charge.
How big is the elementary charge?
Exactly 1.602176634 × 10⁻¹⁹ C, fixed by the 2019 SI definition. One coulomb is about 6.2415 × 10¹⁸ elementary charges.