Electric charge is a fundamental property of matter that causes it to experience a force when placed in an electromagnetic field. It is measured in Coulombs (C) in the SI system. Protons carry positive charge (+e), electrons carry negative charge (-e), and neutrons are neutral. The elementary charge e = 1.602176634 × 10⁻¹⁹ C is the smallest unit of observable charge.
Electric Charge Converter
Convert between Coulomb, Ampere-hour, Faraday, Elementary charge, Statcoulomb, Abcoulomb and 11+ other charge units with scientific precision based on the 2019 SI redefinition.
Conversion Formula
1 Coulomb = 1 Ampere-second
Common Charge Conversions
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What is Electric Charge?
Electric charge is a fundamental property of matter that causes it to experience a force when placed in an electromagnetic field. It is one of the four fundamental properties of matter, alongside mass, spin, and color charge. Charge comes in two types: positive (carried by protons) and negative (carried by electrons). The SI unit of electric charge is the Coulomb (C), defined as the charge transported by a constant current of one Ampere in one second.
Since the 2019 SI redefinition, the elementary charge e has been defined as exactly 1.602176634 × 10⁻¹⁹ Coulombs. This fixed value allows for precise conversions between macroscopic charge units (Coulomb, Ampere-hour) and microscopic units (elementary charge).
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Conservation of Charge Electric charge is conserved in all physical processes — it cannot be created or destroyed, only transferred.
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Quantization Charge exists in discrete multiples of the elementary charge e. All observable charges are integer multiples of e.
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Coulomb's Law The force between two point charges is proportional to the product of their charges and inversely proportional to the square of the distance.
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SI Redefinition 2019 The elementary charge e is now an exact constant: 1.602176634 × 10⁻¹⁹ C, enabling precise metrology.
All Charge Units Explained
Our converter supports 17 electric charge units spanning SI, CGS, practical, and fundamental physics systems. Here's what each unit represents:
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Coulomb (C) SI base unit of charge. 1 C = charge transported by 1 A in 1 s. Named after Charles-Augustin de Coulomb.
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Kilocoulomb (kC) 1,000 Coulombs. Used in industrial applications and large-scale electrical systems.
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Megacoulomb (MC) 1,000,000 Coulombs. Used in lightning research and large capacitor banks.
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MilliCoulomb (mC) 0.001 Coulomb. Common in electronics and small capacitor measurements.
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MicroCoulomb (μC) 10⁻⁶ Coulomb. Widely used in capacitor ratings and electrostatic applications.
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NanoCoulomb (nC) 10⁹ Coulomb. Used in precision electrostatic measurements and particle physics.
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PicoCoulomb (pC) 10⁻¹² Coulomb. Used in high-precision laboratory measurements.
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Ampere-hour (Ah) 3,600 Coulombs. Standard unit for battery capacity. A 1 Ah battery delivers 1 A for 1 hour.
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MilliAmpere-hour (mAh) 3.6 Coulombs. Standard unit for smartphone and small battery capacity ratings.
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Ampere-second (A·s) Exactly 1 Coulomb. Alternative expression of the Coulomb in terms of current and time.
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Ampere-minute (A·min) 60 Coulombs. Used in some industrial electroplating applications.
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Faraday (F) ≈ 96,485.33212 C. Charge of one mole of electrons. Essential in electrochemistry.
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Elementary Charge (e) Exactly 1.602176634 × 10⁻¹⁹ C. Charge of a single proton. Fundamental constant of nature.
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Abcoulomb (abC) Exactly 10 Coulombs. CGS electromagnetic unit. Still used in some physics literature.
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StatCoulomb (statC) ≈ 3.33564 × 10⁻¹⁰ C. CGS electrostatic unit (Franklin). Used in theoretical physics.
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EMU of charge Electromagnetic unit = Abcoulomb = 10 C. Part of the CGS-EMU system.
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ESU of charge Electrostatic unit = Statcoulomb ≈ 3.33564 × 10⁻¹ C. Part of the CGS-ESU system.
Real-World Applications
Electric charge conversions are essential across multiple scientific and engineering disciplines. Here are the most common applications:
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Battery Technology Converting between mAh and Coulombs to compare battery capacities across different rating systems.
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Electrochemistry Using Faraday's constant to calculate quantities in electrolysis, electroplating, and redox reactions.
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Particle Physics Converting between elementary charge units and Coulombs for subatomic particle calculations.
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Electronics Design Calculating capacitor charge storage in μC, nC, or pC for circuit design and analysis.
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Power Engineering Converting between Ah and Coulombs for large-scale energy storage and grid applications.
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Space Technology Charge calculations for satellite batteries, ion thrusters, and plasma propulsion systems.
How to Use This Converter
Our charge converter is engineered for speed, precision, and ease of use. Follow these steps to get accurate conversions instantly.
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Select Source Unit Choose the charge unit you want to convert from (Coulomb, Ah, Faraday, etc.).
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Select Target Unit Choose the charge unit you want to convert to from the second dropdown.
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Enter Value Type your charge value — the result appears instantly as you type.
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View Formula The exact conversion formula is displayed below for verification and learning.
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Swap Units Click the swap button to instantly reverse the conversion direction.
Why Professionals Choose ASLI FORM
Built with precision engineering and premium design, our converter meets the demands of scientists, engineers, and professionals worldwide.
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2019 SI Standard Uses the exact 2019 SI redefinition values for elementary charge and Faraday constant.
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10-Digit Precision Results accurate to 10 significant digits, suitable for research and engineering.
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Works Offline All calculations run locally in your browser. Perfect for laboratory use.
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Universal Compatibility From basic keypad phones to 4K displays — works on every device and OS.
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Zero Tracking No cookies, no analytics, no data collection. Your privacy is absolute.
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Free Forever No subscriptions, no hidden fees, no usage limits, no advertisements.
Frequently Asked Questions
The SI unit of electric charge is the Coulomb (C), named after French physicist Charles-Augustin de Coulomb (1736–1806). One Coulomb equals the charge transported by a constant current of one Ampere in one second: 1 C = 1 A × 1 s. It can also be expressed in terms of the elementary charge: 1 C ≈ 6.242 × 10¹⁸ elementary charges.
The elementary charge (e) is the electric charge carried by a single proton or the magnitude of the negative charge carried by a single electron. Since the 2019 SI redefinition, e has been defined as exactly 1.602176634 × 10⁻¹⁹ Coulombs. This exact value is crucial because it allows for precise conversions between macroscopic charge measurements and the fundamental quantum of charge.
Both measure electric charge, but they serve different practical purposes:
- Coulomb (C) is the SI base unit, used in physics and engineering calculations.
- Ampere-hour (Ah) is a practical unit commonly used for battery capacity ratings.
- The conversion is: 1 Ah = 3,600 C (since 1 hour = 3,600 seconds).
- A typical smartphone battery has 3,000-5,000 mAh = 10,800-18,000 C of charge.
One Faraday (F) is the magnitude of electric charge per mole of electrons, equal to the Faraday constant: 96,485.33212 C/mol. It is named after Michael Faraday and is widely used in electrochemistry for calculating quantities in electrolysis, electroplating, and redox reactions. For example, to deposit 1 mole of silver (Ag⁺ + e⁻ → Ag), you need exactly 1 Faraday of charge.
Statcoulomb (statC), also called the Franklin (Fr), is the CGS electrostatic unit of charge, while Coulomb (C) is the SI unit. The conversion is: 1 statC ≈ 3.33564 × 10⁻¹⁰ C. Statcoulomb is still used in some physics contexts, particularly in older literature and certain theoretical calculations involving the CGS-ESU system.
The Abcoulomb (abC) is the CGS electromagnetic unit of charge, also known as the EMU of charge. It is defined as exactly 10 Coulombs. The abcoulomb is part of the CGS-EMU system and is occasionally encountered in older physics literature and certain theoretical contexts.
To convert milliampere-hours (mAh) to Coulombs, use the formula: C = mAh × 3.6. For example, a 3000 mAh smartphone battery contains 3000 × 3.6 = 10,800 Coulombs of charge. Conversely, to convert Coulombs to mAh: mAh = C ÷ 3.6.
Since the elementary charge e = 1.602176634 × 10⁻¹⁹ C (exactly), one Coulomb contains 1/e ≈ 6.241509074 × 10¹⁸ elementary charges. This is approximately 6.24 quintillion electrons or protons.
The 2019 SI redefinition fixed the value of the elementary charge e at exactly 1.602176634 × 10⁻¹⁹ C. Previously, e was a measured quantity with uncertainty. This change means the Coulomb is now defined in terms of e and the second, rather than through the Ampere. The Faraday constant F = Nₐ × e is now also an exact value: 96,485.33212... C/mol.
Yes. Our converter uses the exact 2019 SI-defined values for the elementary charge and Faraday constant, providing results accurate to 10 significant digits. This level of precision is suitable for research, engineering, academic work, and professional applications. For the most demanding metrology work, consult NIST or BIPM references directly.
Absolutely. Our converter is designed with a mobile-first responsive approach and works perfectly on every device — from basic keypad phones to 4K desktop displays. The interface adapts intelligently: desktops get a sidebar, tablets get a collapsible sidebar, and mobile devices get optimized dropdowns. Touch interactions and momentum scrolling are optimized for mobile.
Yes. Once the page loads, all calculations happen locally in your browser. There is no server-side processing, no API calls, and no internet dependency for conversions. This makes the tool perfect for laboratory work, field research, and anywhere connectivity is limited.
No. We do not collect, store, or transmit any of the values you enter. All calculations happen entirely in your browser's memory and are destroyed the moment you close the tab. We use no analytics scripts, no cookies for tracking, and no third-party services. Your privacy is absolute.
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