How to Convert Electron Volts to Joules

A joule (J) is the unit of energy recommended by the International System of Units (SI). One joule corresponds to energy need to move an object for 1 meter using force of 1 Newton. The electron volt (eV) is not the SI unit, but it is traditionally used in solid-state and nuclear physics. 1 eV corresponds to the kinetic energy gained by an electron accelerated with the electrostatic potential of 1 volt. The formula to convert eV to J is
E(J)=1.60217653E-19 x E(eV).
Consider an example of converting 5.34 eV in J both by hand and with an available web based energy converter.

Things You'll Need

• Calculator

Instructions

1. Use the formula given to calculate energy in joules with the calculator.
   E= 1.60217653E-19 x 5.34 eV = 8.5556226702E-19 J.

2. Navigate to the NASA Energy Converter (see resources).

3. Select "J" as the units using the drop-down listbox in the column "Energy."

4. Select "eV" as the units using the drop-down listbox in the column "electron volt."

5. Enter the energy value in eV in the field in the column "electron volt."
   In our example, enter the value 5.34.

   Note: always do Steps 2 and 3 before entering energy.

6. Click on the data field in the "energy" column. Energy in J should appear there.
   In our example it is 8.5556E-19 J.
   Note: the result is rounded to the 4th digit after the decimal point which very reasonable.

7. Click "Reset," and repeat Steps 3 to 6 to convert another energy value.

Resources

• NASA Energy Converter