Choose charge transfer, capacitor energy, power and time, or a nominal battery estimate, then select the quantity to calculate. Voltage alone does not determine energy.

Constant potential difference: E = VQ. Voltage alone does not determine energy.

Volts to Joules Formula

The following formula is used to convert volts to joules.

J = V × C
  • Where J is the energy (joules)
  • V is the voltage (volts)
  • C is the electrical charge (coulombs)

To calculate joules from volts, multiply the voltage by the electrical charge.

Volts and Coulombs to Joules Conversion Table (J = V × C)
Volts (V) Coulombs (C) Joules (J)
1.50.0010.002
3.30.0010.003
50.0010.005
90.0010.009
120.0010.012
3.70.0100.037
50.0100.050
120.0100.120
240.0100.240
480.0100.480
50.1000.500
120.1001.200
240.1002.400
480.1004.800
50.5002.500
120.5006.000
240.50012.000
91.0009.000
121.00012.000
481.00048.000
Joules are calculated using J = V × C. Examples use common voltages and charges; values rounded to 3 decimals.

Can volts be converted to joules?

Volts cannot be directly converted into joules without extra information because volts measure potential difference and joules measure energy.

To calculate joules from volts you need the charge of the electricity in coulombs. From there, multiply the charge and volts together to get the energy in joules.

How to convert volts to joules?

Example Problem:

The following example outlines how to calculate the total joules from volts.

First, determine the voltage in volts. In this example, the total number of volts is measured to be 500.

Next, determine the electrical charge. In this case, the charge is measured to be 1.5 coulombs.

Finally, calculate the joules using the formula above:

J = V * C

J = 500 * 1.5

J = 750 joules