Title: permittivity of vacuum
Long Title: IUPAC Gold Book - permittivity of vacuum
DOI: 10.1351/goldbook.P04508
Status: current
Index: constant

Definition
Fundamental physical constant \(\varepsilon_{0}=\frac{1}{\mu _{0}\ c_{0}^{2}}\) exactly, where \(\mu_{0}\) is the permeability of vacuum and \(c_{0}\) the speed of light in vacuum. It is equal to \(8.854\ 187\ 817\,...\times\ 10^{-12}\ \rm{F m}^{-1}\).

Related Term
- permeability of vacuum: https://goldbook.iupac.org/terms/view/P04504

Sources
- CODATA 2006 (https://doi.org/10.1103/RevModPhys.80.633)
- Green Book, 2nd ed., p. 14 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/P04508/html
- json: https://goldbook.iupac.org/terms/view/P04508/json
- xml: https://goldbook.iupac.org/terms/view/P04508/xml

Citation: Citation: 'permittivity of vacuum' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.P04508
License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.
Collection: If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .
Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-05-09T22:30:55+00:00