Characteristic impedance of vacuum = 376.730 313 412 Ω

Name: Characteristic impedance of vacuum (Z₀) — CODATA 2022 value
Creator: NIST

Symbol: Z₀
Value: 376.730 313 412
Unit: Ω
Uncertainty: 0.000 000 059
Copy-ready: 376.730313412

μ₀c — the ratio of electric to magnetic field strength in a plane wave travelling through vacuum.

NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.

Universal constants

Reduced Planck constant Newtonian constant of gravitation Standard acceleration of gravity Vacuum electric permittivity Vacuum magnetic permeability Characteristic impedance of vacuum

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