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 121–144 of 355 documents

Document	Version
elementary charge elementary charge = 1.602 176 634 × 10⁻¹⁹ C (CODATA 2022 recommended value, NIST)	v2
elementary charge over h-bar elementary charge over h-bar = 1.519 267 447… × 10¹⁵ A J⁻¹ (CODATA 2022 recommended value, NIST)	v1
Faraday constant Faraday constant = 96 485.332 12… C mol⁻¹ (CODATA 2022 recommended value, NIST)	v2
Fermi coupling constant Fermi coupling constant = 1.166 3787 × 10⁻⁵ GeV⁻² (CODATA 2022 recommended value, NIST)	v2
fine-structure constant fine-structure constant = 7.297 352 5643 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
first radiation constant first radiation constant = 3.741 771 852… × 10⁻¹⁶ W m² (CODATA 2022 recommended value, NIST)	v2
first radiation constant for spectral radiance first radiation constant for spectral radiance = 1.191 042 972… × 10⁻¹⁶ W m² sr⁻¹ (CODATA 2022 recommended value, NIST)	v1
Hartree energy Hartree energy = 4.359 744 722 2060 × 10⁻¹⁸ J (CODATA 2022 recommended value, NIST)	v2
Hartree energy in eV Hartree energy in eV = 27.211 386 245 981 eV (CODATA 2022 recommended value, NIST)	v1
hartree-atomic mass unit relationship hartree-atomic mass unit relationship = 2.921 262 317 97 × 10⁻⁸ u (CODATA 2022 recommended value, NIST)	v1
hartree-electron volt relationship hartree-electron volt relationship = 27.211 386 245 981 eV (CODATA 2022 recommended value, NIST)	v1
hartree-hertz relationship hartree-hertz relationship = 6.579 683 920 4999 × 10¹⁵ Hz (CODATA 2022 recommended value, NIST)	v1
hartree-inverse meter relationship hartree-inverse meter relationship = 2.194 746 313 6314 × 10⁷ m⁻¹ (CODATA 2022 recommended value, NIST)	v1
hartree-joule relationship hartree-joule relationship = 4.359 744 722 2060 × 10⁻¹⁸ J (CODATA 2022 recommended value, NIST)	v1
hartree-kelvin relationship hartree-kelvin relationship = 3.157 750 248 0398 × 10⁵ K (CODATA 2022 recommended value, NIST)	v1
hartree-kilogram relationship hartree-kilogram relationship = 4.850 870 209 5419 × 10⁻³⁵ kg (CODATA 2022 recommended value, NIST)	v1
helion g factor helion g factor = -4.255 250 6995 (CODATA 2022 recommended value, NIST)	v1
helion mag. mom. helion mag. mom. = -1.074 617 551 98 × 10⁻²⁶ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
helion mag. mom. to Bohr magneton ratio helion mag. mom. to Bohr magneton ratio = -1.158 740 980 83 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
helion mag. mom. to nuclear magneton ratio helion mag. mom. to nuclear magneton ratio = -2.127 625 3498 (CODATA 2022 recommended value, NIST)	v2
helion mass helion mass = 5.006 412 7862 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v1
helion mass energy equivalent helion mass energy equivalent = 4.499 539 4185 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
helion mass energy equivalent in MeV helion mass energy equivalent in MeV = 2808.391 611 12 MeV (CODATA 2022 recommended value, NIST)	v1
helion mass in u helion mass in u = 3.014 932 246 932 u (CODATA 2022 recommended value, NIST)	v1

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.