- Symbol
- me
- Value
- 9.109 383 7139 × 10−31
- Unit
- kg
- Uncertainty
- 0.000 000 0028 × 10⁻³¹
- Copy-ready
9.1093837139e-31
Energy equivalent 0.510 998 950 69(16) MeV — the number behind the 511 keV annihilation line.
NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.
Particle and atomic masses
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UsePhysics. "Electron mass — 9.109 383 7139 × 10−31 kg." UsePhysics.com. https://usephysics.com/reference/electron-mass. Value from the 2022 CODATA adjustment (NIST). Accessed [date].