What is the mass of a proton?
The proton mass is m_p = 1.67262192369e-27 kg (uncertainty ±5.1e-37). In energy units it is 938.27208816 MeV/c^2.
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| Value | 1.67262192369e-27 kg |
|---|---|
| Symbol | m_p |
| Energy equivalent | 938.27208816 MeV/c^2 |
| Uncertainty | ±5.1e-37 kg |
| Source | CODATA 2018 |
Frequently asked questions
What is the mass of a proton in kg?
m_p = 1.67262192369e-27 kg, roughly 1836 times the electron mass.
What is the proton mass in MeV?
The proton rest mass is 938.27208816 MeV/c^2.
Is the proton heavier than the neutron?
No. The proton (938.272 MeV/c^2) is slightly lighter than the neutron (939.565 MeV/c^2).
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