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 145–168 of 355 documents

Document	Version
helion molar mass helion molar mass = 3.014 932 250 10 × 10⁻³ kg mol⁻¹ (CODATA 2022 recommended value, NIST)	v1
helion relative atomic mass helion relative atomic mass = 3.014 932 246 932 (CODATA 2022 recommended value, NIST)	v1
helion shielding shift helion shielding shift = 5.996 7029 × 10⁻⁵ (CODATA 2022 recommended value, NIST)	v1
helion-electron mass ratio helion-electron mass ratio = 5495.885 279 84 (CODATA 2022 recommended value, NIST)	v1
helion-proton mass ratio helion-proton mass ratio = 2.993 152 671 552 (CODATA 2022 recommended value, NIST)	v1
hertz-atomic mass unit relationship hertz-atomic mass unit relationship = 4.439 821 6590 × 10⁻²⁴ u (CODATA 2022 recommended value, NIST)	v1
hertz-electron volt relationship hertz-electron volt relationship = 4.135 667 696… × 10⁻¹⁵ eV (CODATA 2022 recommended value, NIST)	v1
hertz-hartree relationship hertz-hartree relationship = 1.519 829 846 0574 × 10⁻¹⁶ E_h (CODATA 2022 recommended value, NIST)	v1
hertz-inverse meter relationship hertz-inverse meter relationship = 3.335 640 951… × 10⁻⁹ m⁻¹ (CODATA 2022 recommended value, NIST)	v1
hertz-joule relationship hertz-joule relationship = 6.626 070 15 × 10⁻³⁴ J (CODATA 2022 recommended value, NIST)	v1
hertz-kelvin relationship hertz-kelvin relationship = 4.799 243 073… × 10⁻¹¹ K (CODATA 2022 recommended value, NIST)	v1
hertz-kilogram relationship hertz-kilogram relationship = 7.372 497 323… × 10⁻⁵¹ kg (CODATA 2022 recommended value, NIST)	v1
hyperfine transition frequency of Cs-133 hyperfine transition frequency of Cs-133 = 9 192 631 770 Hz (CODATA 2022 recommended value, NIST)	v2
inverse fine-structure constant inverse fine-structure constant = 137.035 999 177 (CODATA 2022 recommended value, NIST)	v2
inverse meter-atomic mass unit relationship inverse meter-atomic mass unit relationship = 1.331 025 048 24 × 10⁻¹⁵ u (CODATA 2022 recommended value, NIST)	v1
inverse meter-electron volt relationship inverse meter-electron volt relationship = 1.239 841 984… × 10⁻⁶ eV (CODATA 2022 recommended value, NIST)	v1
inverse meter-hartree relationship inverse meter-hartree relationship = 4.556 335 252 9132 × 10⁻⁸ E_h (CODATA 2022 recommended value, NIST)	v1
inverse meter-hertz relationship inverse meter-hertz relationship = 299 792 458 Hz (CODATA 2022 recommended value, NIST)	v1
inverse meter-joule relationship inverse meter-joule relationship = 1.986 445 857… × 10⁻²⁵ J (CODATA 2022 recommended value, NIST)	v1
inverse meter-kelvin relationship inverse meter-kelvin relationship = 1.438 776 877… × 10⁻² K (CODATA 2022 recommended value, NIST)	v1
inverse meter-kilogram relationship inverse meter-kilogram relationship = 2.210 219 094… × 10⁻⁴² kg (CODATA 2022 recommended value, NIST)	v1
inverse of conductance quantum inverse of conductance quantum = 12 906.403 72… ohm (CODATA 2022 recommended value, NIST)	v1
Josephson constant Josephson constant = 483 597.848 4… × 10⁹ Hz V⁻¹ (CODATA 2022 recommended value, NIST)	v2
joule-atomic mass unit relationship joule-atomic mass unit relationship = 6.700 535 2471 × 10⁹ u (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.