Joules to Volts Calculator

Physics Principles of Electric Potential & Energy

By definition, one Volt is equal to one Joule of energy per one Coulomb of charge.

Core Electromagnetism Formulas

• Voltage Equation: Volts (V) = Joules (J) ÷ Coulombs (C)

• Energy Equation: Joules (J) = Volts (V) × Coulombs (C)

• Charge Equation: Coulombs (C) = Joules (J) ÷ Volts (V)

• Electronvolt Conversion: 1 eV = 1.602176634 × 10^-19 Joules | 1 Joule = 6.242 × 10^18 eV

How to Use This Calculator

Enter your Energy (E) (e.g. 50 in J) and Electric Charge (Q) (e.g. 10 in C). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Formula Reference: Joules to Volts Calculator

Input variables:

energyJoules — Energy (E)

chargeCoulombs — Electric Charge (Q)

Computed outputs:

voltageVolts — Electric Potential Voltage (V)

voltageMillivolts — Voltage in Millivolts

voltageKilovolts — Voltage in Kilovolts

energyElectronvolts — Energy in Electronvolts

Mathematical relationships extracted from calculation logic:

mv = v * 1000

ev = energy * 6.242e18

Standard: NIST Handbook 44 and BIPM SI unit definitions

Worked Example

A capacitor releases 50 Joules of energy while moving 10 Coulombs of charge: The resulting electric potential difference across the terminals is 5.00 Volts (5,000.00 mV).

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.