The NIST Reference on Constants, Units, and Uncertainty
Also known as NIST Reference on Constants, Units, and Uncertainty · Values of Fundamental Physical Constants
This database gives values of the basic constants and conversion factors of physics and chemistry resulting from the 2002 least-squares adjustment of the fundamental physical constants as published by the CODATA Task Group on Fundamental Constants and recommended for international use by CODATA.
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About this database
| Website | https://physics.nist.gov/cuu/Constants/index.html |
|---|---|
| Subjects | Natural Sciences · Chemistry · Physics · Physical and Theoretical Chemistry · Condensed Matter Physics · Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas · Particles, Nuclei and Fields |
| Last updated | 2026-09-11 |