What is the mass of an electron?
The electron mass is m_e = 9.1093837015e-31 kg (uncertainty ±2.8e-40). In energy units it is 0.51099895000 MeV/c^2.
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| Value | 9.1093837015e-31 kg |
|---|---|
| Symbol | m_e |
| Energy equivalent | 0.51099895000 MeV/c^2 |
| Uncertainty | ±2.8e-40 kg |
| Source | CODATA 2018 |
Frequently asked questions
What is the mass of an electron in kg?
m_e = 9.1093837015e-31 kg, about 1/1836 of the proton mass.
What is the electron mass in MeV?
In energy units the electron rest mass is 0.51099895000 MeV/c^2.
Is the electron mass exact?
No. It is measured with a small uncertainty of ±2.8e-40 kg.
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