Electric Charge Converter

Convert between electric charge units including Coulombs, Ampere-hours, elementary charges, and more.

1 C =

0.277778

Milliampere-hours (mAh)

1 C in all units

Coulombs (C)1
Millicoulombs (mC)1,000
Microcoulombs (uC)10,00,000
Nanocoulombs (nC)1.000000e+9
Picocoulombs (pC)1.000000e+12
Ampere-hours (Ah)0.000278
Milliampere-hours (mAh)0.277778
Elementary charges (e)6.242197e+18
Franklins (Fr)2.997602e+9

Quick Reference

1 Coulomb

= 1 A*s

1 Ah

= 3600 C

Symbol

Q (charge)

Electron

= 1.602e-19 C

What is Electric Charge?

Electric charge is a fundamental physical property of matter that causes it to experience a force when placed in an electromagnetic field. Charge exists in two types — positive and negative — and like charges repel while opposite charges attract. The SI unit of electric charge is the coulomb (C), named after French physicist Charles-Augustin de Coulomb. One coulomb represents the charge transported by a constant current of one ampere flowing for one second.

At the atomic level, charge is carried by subatomic particles: protons carry positive charge and electrons carry negative charge. The elementary charge — the charge of a single proton or electron — is approximately 1.602 × 10⁻¹⁹ coulombs. This fundamental constant connects the macroscopic unit of charge to the microscopic world of atoms and particles.

Electric charge is central to all electrical phenomena. Batteries store and release charge, capacitors accumulate charge on their plates, and currents represent the flow of charge through conductors. Understanding charge and its units is essential for electronics, electrical engineering, physics, and any field that involves electricity or magnetism.

Charge Conversion Formula

Electric charge conversion uses factors relative to the SI unit of coulombs (C).

Electric Charge Conversion

Charge_to = Charge_from × (Factor_from / Factor_to)

Where:

  • Charge_from= Charge value in the source unit
  • Factor_from= Conversion factor of source unit to coulombs
  • Factor_to= Conversion factor of target unit to coulombs

Charge Unit Reference

Understanding the relationships between charge units is essential for working across different contexts and industries.

Unit Symbol Value in Coulombs
CoulombC1
MillicoulombmC0.001
MicrocoulombμC10⁻⁶
NanocoulombnC10⁻⁹
PicocoulombpC10⁻¹²
Ampere-hourAh3600
Milliampere-hourmAh3.6
Elementary chargee1.602 × 10⁻¹⁹

How to Use This Calculator

The electric charge converter provides accurate conversions across multiple units:

  1. Enter the charge value: Type any numerical value into the input field.
  2. Select the source unit: Choose from coulombs, millicoulombs, microcoulombs, nanocoulombs, picocoulombs, ampere-hours, milliampere-hours, elementary charges, or franklins.
  3. Select the target unit: Choose the unit you want to convert to.
  4. Swap units: Use the swap button to quickly reverse the conversion direction.
  5. View all conversions: The results panel shows the equivalent value in every supported unit simultaneously.

Quick reference values for common charge relationships are displayed at the bottom.

Real-World Applications

Electric charge conversion is essential in battery technology and energy storage. Battery capacity is typically specified in ampere-hours (Ah) or milliampere-hours (mAh). A smartphone battery rated at 4000 mAh stores 4000 × 3.6 = 14,400 coulombs of charge. Converting between coulombs and ampere-hours helps engineers compare battery capacities and estimate device runtimes.

In semiconductor and electronics design, charge measurements at the nanocoulomb and picocoulomb level are critical. Dynamic RAM stores charge in tiny capacitors, flash memory traps charge in floating gates, and image sensors accumulate charge on photodiode arrays. Understanding charge at these scales is essential for designing and debugging modern integrated circuits.

Physics research and particle physics use elementary charge as a fundamental unit. The charge of individual particles is always an integer multiple of the elementary charge. Experimental measurements of charge quantization, Coulomb's law experiments, and particle accelerator operations all involve converting between macroscopic charge units and elementary charges.

Worked Examples

Converting Coulombs to Ampere-hours

Problem:

Convert 10,800 coulombs to ampere-hours.

Solution Steps:

  1. 1Conversion factor: 1 Ah = 3600 C
  2. 2Divide: 10,800 ÷ 3600 = 3 Ah

Result:

10,800 C = 3 Ah

Converting mAh to Coulombs

Problem:

Convert a 3000 mAh battery capacity to coulombs.

Solution Steps:

  1. 1Conversion factor: 1 mAh = 3.6 C
  2. 2Multiply: 3000 × 3.6 = 10,800 C

Result:

3000 mAh = 10,800 coulombs

Converting Elementary Charges to Coulombs

Problem:

How many coulombs is 1 billion elementary charges?

Solution Steps:

  1. 1Elementary charge: 1 e = 1.602 × 10⁻¹⁹ C
  2. 2Multiply: 10⁹ × 1.602 × 10⁻¹⁹ = 1.602 × 10⁻¹⁰ C

Result:

10⁹ elementary charges ≈ 1.602 × 10⁻¹⁰ C

Tips & Best Practices

  • 1 Ah = 3600 C — this is the key conversion between battery capacity and SI charge
  • Smartphone batteries typically store 10,000-20,000 coulombs (3000-5000 mAh)
  • One coulomb is an enormous number of elementary charges (over 6 quintillion)
  • Elementary charge (1.602 × 10⁻¹⁹ C) is a fundamental constant of nature
  • For battery comparisons, mAh and Ah are more practical than coulombs
  • Charge is always conserved — it cannot be created or destroyed, only transferred

Frequently Asked Questions

Coulombs (C) and ampere-hours (Ah) measure the same thing — electric charge — but at different scales. One ampere-hour equals 3600 coulombs. Coulombs are the SI unit, used in physics and electronics. Ampere-hours are commonly used in battery specifications because they conveniently express the charge capacity of batteries in practical terms.
One coulomb contains approximately 6.242 × 10¹⁸ elementary charges. This is calculated by dividing one coulomb by the elementary charge: 1 C ÷ 1.602 × 10⁻¹⁹ C/e ≈ 6.242 × 10¹⁸ e. This enormous number reflects the extremely small charge carried by individual particles.
The elementary charge (e) is the electric charge carried by a single proton or the magnitude of charge carried by a single electron. Its value is approximately 1.602 × 10⁻¹⁹ coulombs. All observable electric charges are integer multiples of this fundamental constant, a property known as charge quantization.
To convert milliampere-hours to ampere-hours, divide by 1000. For example, a 4000 mAh battery has a capacity of 4 Ah. To convert to coulombs, multiply the mAh value by 3.6 (since 1 mAh = 3.6 C). A 4000 mAh battery stores 4000 × 3.6 = 14,400 coulombs.
The Franklin (Fr), also called the statcoulomb, is the CGS (centimeter-gram-second) unit of electric charge. One Franklin equals approximately 3.336 × 10⁻¹⁰ coulombs. It is rarely used in modern engineering but appears in some theoretical physics contexts and older scientific literature. The conversion between Franklins and coulombs uses the speed of light.

Sources & References

Last updated: 2026-06-06

💡

Help us improve!

How would you rate the Electric Charge Converter?

<>

Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

Source

Formula Source: NIST Guide to SI Units

by National Institute of Standards

UpdatedLast reviewed: May 2026
CheckedFormula checks are based on standard references and internal QA review.