Charge Converter

Convert between electric charge units — coulomb, megacoulomb, kilocoulomb, millicoulomb, microcoulomb, ampere-hour, faraday, elementary charge, abcoulomb, statcoulomb, and franklin.

Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.

Value

From

Result

1 C = 0.00027777778 A·h

1 Coulomb = 0.00027777778 Ampere-Hours

1 Ampere-Hour = 3600 Coulombs

1 C in every supported unit

What is a Charge Converter?

Electric charge is a fundamental property of matter — the source of every electric and magnetic interaction — and its SI unit is the coulomb (C), defined as the charge carried by a steady one-ampere current flowing for one second. Charge shows up across wildly different scales: a single electron carries only about 1.6×10⁻¹⁹ coulomb (the elementary charge), a phone battery stores a few thousand milliampere-hours (a few coulombs times thousands), a car battery is rated in tens of ampere-hours (tens of thousands of coulombs), and a single lightning strike can transfer several coulombs to tens of coulombs to the ground in a fraction of a second. Because engineers, chemists, and physicists each gravitated toward the unit that best matched their own working scale — batteries in ampere-hours, electrochemistry in faradays, particle physics in elementary charges, older CGS-based physics in abcoulombs and statcoulombs — a single converter that ties them all back to the coulomb is genuinely useful.

This converter is used whenever a charge figure needs to move between those worlds: translating a battery's ampere-hour rating into raw coulombs for a circuit calculation, converting a chemistry problem's moles-of-electrons into faradays and then coulombs, or reading older electromagnetism literature that expresses charge in the CGS system's abcoulomb, statcoulomb, or franklin instead of the modern SI coulomb. Every unit below is defined relative to the coulomb, so any two charge units — modern or historical, SI or CGS — convert directly and consistently.

Conversion chart: Coulomb to Ampere-Hours

Conversion table

Coulomb (C)	Ampere-Hour (A·h)
0.01 C	2.77778E-06 A·h
0.1 C	2.77778E-05 A·h
1 C	0.00027777778 A·h
2 C	0.00055555556 A·h
3 C	0.00083333333 A·h
5 C	0.0013888889 A·h
10 C	0.0027777778 A·h
20 C	0.0055555556 A·h
50 C	0.013888889 A·h
100 C	0.027777778 A·h
1000 C	0.27777778 A·h

Supported Units

Unit	Symbol	In Coulomb
Megacoulomb	MC	1000000 C
Kilocoulomb	kC	1000 C
Coulomb	C	1 C
Millicoulomb	mC	0.001 C
Microcoulomb	µC	1E-06 C
Nanocoulomb	nC	1E-09 C
Picocoulomb	pC	1E-12 C
Abcoulomb	abC	10 C
EMU of Charge	EMU	10 C
Statcoulomb	statC	3.33564E-10 C
ESU of Charge	ESU	3.33564E-10 C
Franklin	Fr	3.33564E-10 C
Ampere-Hour	A·h	3600 C
Ampere-Minute	A·min	60 C
Ampere-Second	A·s	1 C
Faraday	F	96485.309 C
Elementary Charge	e	1.60218E-19 C

About These Parameters

Value: The amount of electric charge you want to convert, expressed in the "From" unit. Accepts decimals, and can represent anything from a single elementary charge to a battery's full ampere-hour rating.
From Unit: The unit your input value is currently measured in — a battery datasheet's ampere-hour rating, an electrochemistry problem's faradays, or an older physics text's abcoulomb or statcoulomb figure.
To Unit: The unit you want the result converted into. Use the swap button to flip From and To instantly, which is handy when translating a historical CGS-system figure into the modern SI coulomb or vice versa.

How Charge Conversion Works

The Formula

Every unit here is defined by a fixed multiplier relative to the coulomb. To convert a value from one unit to another:

result = value × (factor of "From" unit ÷ factor of "To" unit)

For Coulomb → Ampere-Hour: multiply by 0.00027777778. For example, 1 C × 0.00027777778 = 0.00027777778 A·h.

From CGS Charge Units to the SI Coulomb

Before the SI system unified electricity around the ampere and coulomb, 19th-century physicists working in the centimeter-gram-second (CGS) system built two competing "natural" families of electrical units: the electrostatic (ESU) family, whose charge unit is the statcoulomb (also called the franklin, honoring Benjamin Franklin), defined so that two one-statcoulomb charges one centimeter apart repel with exactly one dyne of force; and the electromagnetic (EMU) family, whose charge unit is the abcoulomb, equal to a much larger 10 coulombs. Both systems made Maxwell's equations take a cleaner mathematical form than SI does, which is why some theoretical-physics and plasma-physics literature still uses Gaussian (CGS) units today — this converter lets you move any of those historical figures straight into the modern coulomb.

Why Batteries, Chemistry, and Physics Each Use a Different Unit

Battery engineers rate capacity in ampere-hours because that's literally how a battery is specified and discharged — a steady current for a certain duration. Electrochemists use the faraday because Faraday's laws of electrolysis relate charge passed directly to moles of substance deposited or liberated at an electrode, so working in "moles of charge" (faradays) keeps the chemistry intuitive. Particle physicists use the elementary charge because it's the smallest indivisible unit of free charge in nature, making it the natural yardstick for counting electrons, protons, or ionization events one at a time. All three units describe exactly the same physical quantity — they just scale it to whatever a given field actually measures day to day.

Example

A charge of 1 C equals 0.00027777778 A·h. For scale, a typical smartphone battery stores roughly 3,000-5,000 milliampere-hours (around 10,000-18,000 coulombs), a car battery is rated around 50-100 ampere-hours (180,000-360,000 coulombs), and a single lightning strike transfers on the order of 15-30 coulombs to the ground in well under a second.

Frequently Asked Questions

What's the difference between a coulomb and an ampere-hour?

Both measure electric charge, but on very different scales. A coulomb is the charge moved by one ampere in one second; an ampere-hour is the charge moved by one ampere over a full hour, which is 3,600 times larger. Batteries are rated in ampere-hours (or milliampere-hours) because that matches how they're actually discharged, while raw coulombs are more common in circuit-level physics calculations.

Why are abcoulomb and EMU of charge the same value?

"EMU of charge" is simply the generic name for the CGS electromagnetic system's charge unit, and "abcoulomb" is that same unit's specific name — they're not two different quantities, just two names for one unit, both equal to 10 coulombs. The same relationship holds for statcoulomb, ESU of charge, and franklin, which are three names for the same CGS electrostatic charge unit.

How is the faraday related to the elementary charge?

The faraday is the charge of one full mole of elementary charges — multiply Avogadro's number (about 6.022×10²³) by the elementary charge (about 1.602×10⁻¹⁹ coulomb) and you get the Faraday constant, roughly 96,485 coulombs per mole. It's the bridge electrochemists use between "how many electrons were transferred" and "how much charge passed through the circuit."

Is the elementary charge the smallest possible amount of charge?

For any freely existing particle, yes — every electron and proton carries exactly one elementary charge (with opposite sign), and no isolated particle has ever been observed with a smaller fraction of it. Quarks carry fractional charges of ±1/3 or ±2/3 of the elementary charge, but they're never observed in isolation, only bound inside composite particles whose overall charge is always a whole multiple of the elementary charge.

Possible Charge Conversions