Classical electron radius = 2.817 940 3205 × 10−15 m
- Symbol
- re
- Value
- 2.817 940 3205 × 10−15
- Unit
- m
- Uncertainty
- 0.000 000 0013 × 10⁻¹⁵
- Copy-ready
2.8179403205e-15
A convenient length, not a physical size — the electron has no measured extent.
NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.
Atomic and electromagnetic constants
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