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Electronvolts to Joules Converter.

Convert electronvolts to joules.

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Joules (J): 1.60217663e-19

Joules (J)

1.60217663e-19

Uses the exact SI elementary-charge value: 1 eV = 1.602176634 × 10⁻¹⁹ J.

FAQs

How does the electronvolts to joules converter work?

Convert electronvolts to joules.

Use Cases

Particle Physics Calculations

Convert particle energies from electronvolts to joules for experiments, data analysis, or theoretical work in high-energy physics.

Example: Convert 5 GeV (5 × 10^9 eV) to joules: 5 × 10^9 eV × 1.602 × 10^-19 J/eV = 8.01 × 10^-10 J.

Quantum Chemistry and Spectroscopy

When working with molecular or atomic energy levels, convert ionization energies or photon energies from eV to joules for calculations involving the Boltzmann constant or Planck's constant.

Example: Convert 13.6 eV (hydrogen ionization energy) to joules: 13.6 × 1.602 × 10^-19 = 2.18 × 10^-18 J.

Frequently Asked Questions

What is an electronvolt?
An electronvolt (eV) is a unit of energy equal to the amount of kinetic energy gained by a single electron when it is accelerated through an electric potential difference of one volt. It is commonly used in particle physics and quantum mechanics.
How do I convert electronvolts to joules?
To convert electronvolts to joules, multiply the number of electronvolts by the conversion factor 1.602176634 × 10^-19. For example, 1 eV = 1.602176634 × 10^-19 J. Use the converter to get instant results.
Why is the electronvolt used instead of joules?
The electronvolt is a more convenient unit for describing energies at the atomic and subatomic scale, where joules are impractically large. For instance, the energy of a single photon in visible light is a few electronvolts, but in joules it is an extremely small number.

Tips & Common Mistakes

Tips

  • Remember that 1 eV = 1.602176634 × 10^-19 J exactly. Use this constant for precise conversions.
  • For large or small numbers, use scientific notation to avoid errors. For example, 1 MeV = 1 × 10^6 eV.
  • Double-check your input: ensure you are entering the value in electronvolts, not kiloelectronvolts (keV) or megaelectronvolts (MeV), unless you intend to convert those units first.

Common Mistakes to Avoid

  • Forgetting to multiply by the conversion factor; simply changing the unit without multiplying leads to incorrect results.
  • Mixing up the direction of conversion: this converter is for eV to J, not J to eV. If you need the reverse, use a separate tool.
  • Using an outdated or rounded conversion factor (e.g., 1.6 × 10^-19) when high precision is required.

Last updated: August 13, 2026