CODATA fundamental physical constants

CODATA 2022 recommended values of the fundamental physical constants, published by NIST (a US government work). One document per constant citing the NIST complete listing; refreshed on each CODATA release, roughly every four years.

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Documents

Showing 49–72 of 355 documents

Document	Version
Bohr magneton in K/T Bohr magneton in K/T = 0.671 713 814 72 K T⁻¹ (CODATA 2022 recommended value, NIST)	v1
Bohr radius Bohr radius = 5.291 772 105 44 × 10⁻¹¹ m (CODATA 2022 recommended value, NIST)	v2
Boltzmann constant Boltzmann constant = 1.380 649 × 10⁻²³ J K⁻¹ (CODATA 2022 recommended value, NIST)	v2
Boltzmann constant in eV/K Boltzmann constant in eV/K = 8.617 333 262… × 10⁻⁵ eV K⁻¹ (CODATA 2022 recommended value, NIST)	v1
Boltzmann constant in Hz/K Boltzmann constant in Hz/K = 2.083 661 912… × 10¹⁰ Hz K⁻¹ (CODATA 2022 recommended value, NIST)	v1
Boltzmann constant in inverse meter per kelvin Boltzmann constant in inverse meter per kelvin = 69.503 480 04… m⁻¹ K⁻¹ (CODATA 2022 recommended value, NIST)	v1
characteristic impedance of vacuum characteristic impedance of vacuum = 376.730 313 412 ohm (CODATA 2022 recommended value, NIST)	v2
classical electron radius classical electron radius = 2.817 940 3205 × 10⁻¹⁵ m (CODATA 2022 recommended value, NIST)	v2
Compton wavelength Compton wavelength = 2.426 310 235 38 × 10⁻¹² m (CODATA 2022 recommended value, NIST)	v2
conductance quantum conductance quantum = 7.748 091 729… × 10⁻⁵ S (CODATA 2022 recommended value, NIST)	v2
conventional value of ampere-90 conventional value of ampere-90 = 1.000 000 088 87… A (CODATA 2022 recommended value, NIST)	v1
conventional value of coulomb-90 conventional value of coulomb-90 = 1.000 000 088 87… C (CODATA 2022 recommended value, NIST)	v1
conventional value of farad-90 conventional value of farad-90 = 0.999 999 982 20… F (CODATA 2022 recommended value, NIST)	v1
conventional value of henry-90 conventional value of henry-90 = 1.000 000 017 79… H (CODATA 2022 recommended value, NIST)	v1
conventional value of Josephson constant conventional value of Josephson constant = 483 597.9 × 10⁹ Hz V⁻¹ (CODATA 2022 recommended value, NIST)	v1
conventional value of ohm-90 conventional value of ohm-90 = 1.000 000 017 79… ohm (CODATA 2022 recommended value, NIST)	v1
conventional value of volt-90 conventional value of volt-90 = 1.000 000 106 66… V (CODATA 2022 recommended value, NIST)	v1
conventional value of von Klitzing constant conventional value of von Klitzing constant = 25 812.807 ohm (CODATA 2022 recommended value, NIST)	v1
conventional value of watt-90 conventional value of watt-90 = 1.000 000 195 53… W (CODATA 2022 recommended value, NIST)	v1
Copper x unit Copper x unit = 1.002 076 97 × 10⁻¹³ m (CODATA 2022 recommended value, NIST)	v1
deuteron g factor deuteron g factor = 0.857 438 2335 (CODATA 2022 recommended value, NIST)	v1
deuteron mag. mom. deuteron mag. mom. = 4.330 735 087 × 10⁻²⁷ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
deuteron mag. mom. to Bohr magneton ratio deuteron mag. mom. to Bohr magneton ratio = 4.669 754 568 × 10⁻⁴ (CODATA 2022 recommended value, NIST)	v2
deuteron mag. mom. to nuclear magneton ratio deuteron mag. mom. to nuclear magneton ratio = 0.857 438 2335 (CODATA 2022 recommended value, NIST)	v2

Source, review, and usage

Published on Koskamo by: Koskamo
Version: 468
Documents: 355 documents
Reviewed: 2026-10-03
Last approved change: 2026-10-04
Agent lookups: 71 in the last 90 days
Reuse: CODATA 2022 recommended values from NIST, a work of the US government (public domain in the United States)
Review status: Published by Koskamo; proposed revisions require Koskamo approval

Original sources are linked on each document. Owner approval records a publishing decision; it does not imply independent fact checking.

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Change history

Every change that reached this dataset. Proposals from contributors land only after Koskamo approves them.

Approved revision2026-10-04
Wien wavelength displacement law constant · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
weak mixing angle · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
von Klitzing constant · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
vacuum mag. permeability · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
vacuum electric permittivity · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
unified atomic mass unit · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton to proton mag. mom. ratio · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton mag. mom. to nuclear magneton ratio · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton mag. mom. to Bohr magneton ratio · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.
Approved revision2026-10-04
triton mag. mom. · v2
Proposed by codata-seed
Regenerated from the CODATA 2022 NIST listing.