Volt to eV Calculator

Convert voltage to electronvolts (eV) and vice versa. Essential physics tool for electronics, particle physics, and quantum mechanics.

Volt → eV
eV → Volt

Conversion Formula: 1 eV = 1.602176634×10⁻¹⁹ J

For an electron: E(eV) = V (since e = 1.602×10⁻¹⁹ C)

For a particle with charge q: E(eV) = q × V / e

Enter the voltage in volts (V)
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Select the particle charge in elementary charge units
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Understanding Electronvolts (eV)

The electronvolt (eV) is a unit of energy equal to approximately 1.602×10⁻¹⁹ joules. It is defined as the amount of kinetic energy gained by a single electron accelerating from rest through an electric potential difference of one volt in vacuum.

Mathematical Definition:

1 eV = e × 1 V = 1.602176634×10⁻¹⁹ J

where e is the elementary charge (1.602176634×10⁻¹⁹ coulombs).

Common Energy Scales in eV

Energy Range Typical Applications Example Values
meV (millielectronvolts) Atomic vibrations, thermal energy 25 meV at room temperature
eV (electronvolts) Atomic physics, chemical bonds 13.6 eV (hydrogen ionization)
keV (kiloelectronvolts) X-rays, electron microscopy 8 keV (copper Kα X-ray)
MeV (megaelectronvolts) Nuclear physics, medical radiation 1.022 MeV (electron rest mass)
GeV (gigaelectronvolts) Particle physics, accelerators 0.938 GeV (proton rest mass)
TeV (teraelectronvolts) High-energy particle physics 6.5 TeV (LHC proton energy)

Applications of Electronvolts

1

Particle Physics: eV units conveniently express the masses and energies of subatomic particles. The rest mass of an electron is about 0.511 MeV/c².

2

Atomic Physics: Electron binding energies in atoms are typically in the eV range. For example, the ionization energy of hydrogen is 13.6 eV.

3

Semiconductor Physics: Band gaps in semiconductors are expressed in eV. Silicon has a band gap of 1.1 eV at room temperature.

Conversion to Other Energy Units

  • Joules: 1 eV = 1.602176634×10⁻¹⁹ J
  • Calories: 1 eV ≈ 3.829×10⁻²⁰ cal
  • Kilowatt-hours: 1 eV ≈ 4.450×10⁻²⁶ kWh
  • Hartree: 1 eV ≈ 0.03675 Hartree (atomic units)
  • Kelvin: 1 eV ≈ 11604.5 K (temperature equivalent)
  • Wavenumber (cm⁻¹): 1 eV ≈ 8065.54 cm⁻¹

Calculator Features:

  • Convert both directions: Volts to eV and eV to Volts
  • Support for different particle charges (electrons, protons, alpha particles, custom)
  • Compare with common energy values in physics
  • Visualize the energy on a logarithmic scale
  • Includes conversion to joules and other units

Frequently Asked Questions

By definition, 1 electronvolt is the energy gained by an electron when it accelerates through a potential difference of 1 volt. The energy gained is E = qV, where q is the electron's charge (1.602×10⁻¹⁹ C) and V is the voltage. So E = (1.602×10⁻¹⁹ C) × 1 V = 1.602×10⁻¹⁹ J, which is exactly 1 eV.

Yes! The calculator includes options for different particle charges. For a particle with charge q (in units of elementary charge), the energy in eV is E(eV) = q × V. For example, a proton (charge +e) accelerated through 1000 V gains 1000 eV of energy. An alpha particle (charge +2e) accelerated through 1000 V gains 2000 eV.

Volts (V) measure electric potential difference or voltage. Electronvolts (eV) measure energy. They are related by the formula E(eV) = qV for a particle with charge q (in elementary charge units). For an electron (q=1), 1 V gives 1 eV of energy. They are different physical quantities with different dimensions.

In semiconductor physics, the band gap (energy difference between valence and conduction bands) is typically expressed in eV. Common band gaps: Silicon (1.1 eV), Germanium (0.67 eV), Gallium Arsenide (1.43 eV). Also, the built-in potential of p-n junctions and the threshold voltage of transistors are often given in volts, which can be converted to eV for electron energy calculations.

13.6 eV is the ionization energy of a hydrogen atom in its ground state. This is the minimum energy required to remove the electron from a hydrogen atom. It's a fundamental constant in atomic physics and serves as a reference point for other atomic energy levels.