Charge Converter
Convert electric charge between coulomb, its metric prefixes, ampere-hour, ampere-minute, ampere-second, faraday, elementary charge and the CGS units statcoulomb and abcoulomb. Pick two units, enter a value and read the result instantly.
Select two units to see the conversion factor.
This tool converts electric charge (C) only. It is not electric current (A, charge per second) and not charge density (charge per length, area or volume). Ampere-hours are a unit of charge, not of energy.
Electric Charge Formula
Every charge unit is a fixed multiple of the coulomb. Result = value × (source factor ÷ target factor). Exact building blocks: 1 A·s = 1 C, so 1 A·h = 3,600 C and 1 A·min = 60 C; 1 abcoulomb = 10 C; 1 statcoulomb (= 1 franklin) = 1/2,997,924,580 C; the elementary charge is exactly 1.602176634 × 10⁻¹⁹ C; and one faraday is the charge of one mole of elementary charges, NA × e = 96,485.33212… C.
What Is Electric Charge?
Electric charge is the property of matter that makes it feel a force in an electric field. It comes in two kinds, positive and negative, and like charges repel while opposite charges attract. Electrons carry a negative charge of one elementary charge, protons carry the same amount with a positive sign, and every free charge in nature is a whole multiple of that amount.
The SI unit is the coulomb (C), the charge carried past a point by a steady current of one ampere in one second. That is why an ampere-second equals a coulomb. One coulomb is about 6.24 × 10¹⁸ elementary charges, so everyday static electricity involves only nanocoulombs to microcoulombs, a lightning stroke carries a few tens of coulombs, and a phone battery moves thousands of coulombs when it discharges.
The ampere-hour (A·h) is the practical unit for batteries. A 3 A·h cell can deliver 3 A for one hour, which is 10,800 C. For a battery rated in milliampere-hours, divide by 1,000 first: 3,000 mAh is 3 A·h. The faraday is the charge of one mole of electrons and links charge to chemistry through Faraday’s laws of electrolysis. The statcoulomb (also called the franklin or the ESU of charge) and the abcoulomb (the EMU of charge) belong to the older CGS systems and still appear in physics texts that use Gaussian units.
Charge is not the same as current, which is charge per unit time, or charge density, which is charge per length, area or volume. This converter changes charge units only. For the rate of flow see the Current Converter.
Supported Units
This converter supports the following 17 charge units. The last column gives the value of each unit in the base unit, the coulomb. Several CGS names are identical in size: the abcoulomb equals the EMU of charge, and the statcoulomb equals the franklin and the ESU of charge.
| Unit | Symbol | Value in C |
|---|---|---|
| Coulomb | C | 1 |
| Megacoulomb | MC | 1,000,000 |
| Kilocoulomb | kC | 1,000 |
| Millicoulomb | mC | 0.001 |
| Microcoulomb | µC | 1e-6 |
| Nanocoulomb | nC | 1e-9 |
| Picocoulomb | pC | 1e-12 |
| Abcoulomb | abC | 10 |
| EMU of charge | EMU | 10 |
| Statcoulomb | statC | 3.335640952e-10 |
| ESU of charge | ESU | 3.335640952e-10 |
| Franklin | Fr | 3.335640952e-10 |
| Ampere-hour | A·h | 3,600 |
| Ampere-minute | A·min | 60 |
| Ampere-second | A·s | 1 |
| Faraday (carbon-12 scale) | faraday | 96,485.33212 |
| Elementary charge | e | 1.602176634e-19 |
How to Use the Charge Converter
- Type the electric charge in the value box. Decimals and scientific notation such as 0.0025 or 2.5e-3 are accepted.
- Choose the From unit and the To unit.
- The result appears instantly, or press Convert Now. Very large or very small results are shown in scientific notation.
- Use Swap Units to reverse the conversion, Copy Result to copy the answer, open Show this value in all units for a full list, and Clear to start again.
Step-by-step by hand
- Find the size of each unit in the common base unit (C): 1 A·h = 3,600 C and 1 C = 1 C.
- Divide the source size by the target size to get the conversion factor: 3,600 ÷ 1 = 3,600, so 1 A·h = 3,600 C.
- Multiply by your value: 2.5 A·h × 3,600 = 9,000 C.
Charge can be positive or negative, so a minus sign is accepted. Zero is also valid.
Common Charge Conversions
- Battery capacity: a 3,000 mAh battery holds 3 A·h, which is 10,800 C.
- Ampere-hour to kilocoulomb: a 60 A·h car battery holds 216 kC.
- Static electricity: 5 µC equals 5,000 nC and 5,000,000 pC.
- Elementary charges: 1 C equals 6.241509074e+18 elementary charges.
- Electrochemistry: 1 faraday equals 26.80148115 A·h.
- CGS to SI: 1 abcoulomb equals 10 C and 1 statcoulomb equals 3.335640952e-10 C.
Ampere-Hour to Other Charge Units
Quick reference for frequently used values
| A·h | Coulomb (C) | Kilocoulomb (kC) | A·min |
|---|---|---|---|
| 0.001 | 3.6 | 0.0036 | 0.06 |
| 0.01 | 36 | 0.036 | 0.6 |
| 0.1 | 360 | 0.36 | 6 |
| 1 | 3,600 | 3.6 | 60 |
| 2.5 | 9,000 | 9 | 150 |
| 5 | 18,000 | 18 | 300 |
| 10 | 36,000 | 36 | 600 |
| 50 | 180,000 | 180 | 3,000 |
| 100 | 360,000 | 360 | 6,000 |
Where and Why This Conversion Is Used
- Batteries and power banks: capacity is quoted in mAh or A·h, while physics problems and datasheets for supercapacitors use coulombs.
- Electrochemistry: electroplating, electrolysis and corrosion calculations multiply charge in coulombs or faradays by the electrode reaction to find mass.
- Electrostatics and ESD: charge on a person, a capacitor or a charged surface is measured in nanocoulombs and microcoulombs.
- Particle and atomic physics: total charge is counted in elementary charges.
- Reading older literature: Gaussian and electromagnetic CGS texts give charge in statcoulombs or abcoulombs.
Limitations
- Charge in A·h cannot be turned into energy (Wh) without knowing the voltage.
- The ampere-hour, ampere-minute and ampere-second are units of charge only; this tool does not convert them to current.
Important Differences Between Related Electrical Measurements
- Charge, C is an amount. Current, A is the rate: 1 A = 1 C per second. A charge of 3,600 C is delivered by 1 A in an hour, or by 3,600 A in a second.
- Charge vs charge density: density spreads charge over a length (C/m), an area (C/m²) or a volume (C/m³). Total charge is the density multiplied by the length, area or volume it occupies.
- Charge vs energy: an ampere-hour is not a watt-hour. Energy = charge × voltage, so 3 A·h at 3.7 V stores 11.1 Wh.
- Charge vs capacitance: capacitance is charge stored per volt, C = Q ÷ V, measured in farads, not coulombs.
Each converter on this site changes units within one quantity only, and none of them mixes quantities. The related tools are: Charge, Current, Linear Charge Density, Surface Charge Density, Volume Charge Density, Linear Current Density, Surface Current Density, Electric Field Strength, Electric Potential, Electric Resistance, Electric Resistivity, Electric Conductance, Electric Conductivity, Electrostatic Capacitance and Inductance.