Proton mass = 1.672 621 925 95 × 10−27 kg
- Symbol
- mp
- Value
- 1.672 621 925 95 × 10−27
- Unit
- kg
- Uncertainty
- 0.000 000 000 52 × 10⁻²⁷
- Copy-ready
1.67262192595e-27
Energy equivalent 938.272 089 43(29) MeV.
NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.
Particle and atomic masses
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UsePhysics. "Proton mass — 1.672 621 925 95 × 10−27 kg." UsePhysics.com. https://usephysics.com/reference/proton-mass. Value from the 2022 CODATA adjustment (NIST). Accessed [date].