Convert Electronvolts to Millijoules
Convert Electronvolts (eV) to Millijoules (mJ) instantly and accurately.
Conversion Formula
mJ = eV × 1.602176634e-16
About Electronvolts
An electronvolt (eV) is the kinetic energy gained by one electron accelerated through 1 volt - exactly 1.602176634 × 10⁻¹⁹ J (fixed by the 2019 SI revision). It is the natural energy unit of atomic and particle physics: visible light photons carry 1.7-3.1 eV; hydrogen ionisation requires 13.6 eV; X-ray photons span 100 eV-100 keV; protons at the LHC reach 6.5 TeV. Rest masses use eV/c²: electron 0.511 MeV, proton 938.3 MeV, Higgs boson 125 GeV. Nuclear binding energy peaks at ~8 MeV/nucleon for iron-56. 1 eV = 1.602176634 × 10⁻¹⁹ J.
About Millijoules
A millijoule (mJ) is 10⁻³ J - the scale of surgical lasers, spark ignition, and the kinetic energy of small everyday objects. Nd:YAG lasers for ophthalmology and tattoo removal deliver 10-200 mJ per pulse. The minimum spark energy to ignite methane-air is ~0.29 mJ; an automotive spark plug discharges 30-60 mJ per cycle. A 2 g mosquito flying at 1 m/s has kinetic energy ½ × 0.002 × 1² = 1 mJ. Electrocautery monopolar pulses deliver 50-500 mJ to coagulate blood vessels. 1 mJ = 10⁻³ J = 0.2390 cal.
Quick Reference Table
| Electronvolts (eV) | Millijoules (mJ) |
|---|---|
| 1 eV | 1.602 × 10-16 mJ |
| 2 eV | 3.204 × 10-16 mJ |
| 5 eV | 8.011 × 10-16 mJ |
| 10 eV | 1.602 × 10-15 mJ |
| 25 eV | 4.005 × 10-15 mJ |
| 50 eV | 8.011 × 10-15 mJ |
| 100 eV | 1.602 × 10-14 mJ |