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 313–336 of 355 documents

Document	Version
shielded proton gyromag. ratio in MHz/T shielded proton gyromag. ratio in MHz/T = 42.576 385 43 MHz T⁻¹ (CODATA 2022 recommended value, NIST)	v2
shielded proton mag. mom. shielded proton mag. mom. = 1.410 570 5830 × 10⁻²⁶ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
shielded proton mag. mom. to Bohr magneton ratio shielded proton mag. mom. to Bohr magneton ratio = 1.520 993 1551 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
shielded proton mag. mom. to nuclear magneton ratio shielded proton mag. mom. to nuclear magneton ratio = 2.792 775 648 (CODATA 2022 recommended value, NIST)	v2
shielding difference of d and p in HD shielding difference of d and p in HD = 1.987 70 × 10⁻⁸ (CODATA 2022 recommended value, NIST)	v1
shielding difference of t and p in HT shielding difference of t and p in HT = 2.394 50 × 10⁻⁸ (CODATA 2022 recommended value, NIST)	v1
speed of light in vacuum speed of light in vacuum = 299 792 458 m s⁻¹ (CODATA 2022 recommended value, NIST)	v2
standard acceleration of gravity standard acceleration of gravity = 9.806 65 m s⁻² (CODATA 2022 recommended value, NIST)	v2
standard atmosphere standard atmosphere = 101 325 Pa (CODATA 2022 recommended value, NIST)	v2
standard-state pressure standard-state pressure = 100 000 Pa (CODATA 2022 recommended value, NIST)	v1
Stefan-Boltzmann constant Stefan-Boltzmann constant = 5.670 374 419… × 10⁻⁸ W m⁻² K⁻⁴ (CODATA 2022 recommended value, NIST)	v2
tau Compton wavelength tau Compton wavelength = 6.977 71 × 10⁻¹⁶ m (CODATA 2022 recommended value, NIST)	v1
tau energy equivalent tau energy equivalent = 1776.86 MeV (CODATA 2022 recommended value, NIST)	v1
tau mass tau mass = 3.167 54 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v1
tau mass energy equivalent tau mass energy equivalent = 2.846 84 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
tau mass in u tau mass in u = 1.907 54 u (CODATA 2022 recommended value, NIST)	v1
tau molar mass tau molar mass = 1.907 54 × 10⁻³ kg mol⁻¹ (CODATA 2022 recommended value, NIST)	v1
tau-electron mass ratio tau-electron mass ratio = 3477.23 (CODATA 2022 recommended value, NIST)	v1
tau-muon mass ratio tau-muon mass ratio = 16.8170 (CODATA 2022 recommended value, NIST)	v1
tau-neutron mass ratio tau-neutron mass ratio = 1.891 15 (CODATA 2022 recommended value, NIST)	v1
tau-proton mass ratio tau-proton mass ratio = 1.893 76 (CODATA 2022 recommended value, NIST)	v1
Thomson cross section Thomson cross section = 6.652 458 7051 × 10⁻²⁹ m² (CODATA 2022 recommended value, NIST)	v2
triton g factor triton g factor = 5.957 924 930 (CODATA 2022 recommended value, NIST)	v1
triton mag. mom. triton mag. mom. = 1.504 609 5178 × 10⁻²⁶ J T⁻¹ (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.