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 1–24 of 355 documents

Document	Version
alpha particle mass alpha particle mass = 6.644 657 3450 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v2
alpha particle mass energy equivalent alpha particle mass energy equivalent = 5.971 920 1997 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
alpha particle mass energy equivalent in MeV alpha particle mass energy equivalent in MeV = 3727.379 4118 MeV (CODATA 2022 recommended value, NIST)	v1
alpha particle mass in u alpha particle mass in u = 4.001 506 179 129 u (CODATA 2022 recommended value, NIST)	v1
alpha particle molar mass alpha particle molar mass = 4.001 506 1833 × 10⁻³ kg mol⁻¹ (CODATA 2022 recommended value, NIST)	v1
alpha particle relative atomic mass alpha particle relative atomic mass = 4.001 506 179 129 (CODATA 2022 recommended value, NIST)	v1
alpha particle rms charge radius alpha particle rms charge radius = 1.6785 × 10⁻¹⁵ m (CODATA 2022 recommended value, NIST)	v1
alpha particle-electron mass ratio alpha particle-electron mass ratio = 7294.299 541 71 (CODATA 2022 recommended value, NIST)	v1
alpha particle-proton mass ratio alpha particle-proton mass ratio = 3.972 599 690 252 (CODATA 2022 recommended value, NIST)	v1
Angstrom star Angstrom star = 1.000 014 95 × 10⁻¹⁰ m (CODATA 2022 recommended value, NIST)	v1
atomic mass constant atomic mass constant = 1.660 539 068 92 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v2
atomic mass constant energy equivalent atomic mass constant energy equivalent = 1.492 418 087 68 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
atomic mass constant energy equivalent in MeV atomic mass constant energy equivalent in MeV = 931.494 103 72 MeV (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-electron volt relationship atomic mass unit-electron volt relationship = 9.314 941 0372 × 10⁸ eV (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-hartree relationship atomic mass unit-hartree relationship = 3.423 177 6922 × 10⁷ E_h (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-hertz relationship atomic mass unit-hertz relationship = 2.252 342 721 85 × 10²³ Hz (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-inverse meter relationship atomic mass unit-inverse meter relationship = 7.513 006 6209 × 10¹⁴ m⁻¹ (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-joule relationship atomic mass unit-joule relationship = 1.492 418 087 68 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-kelvin relationship atomic mass unit-kelvin relationship = 1.080 954 020 67 × 10¹³ K (CODATA 2022 recommended value, NIST)	v1
atomic mass unit-kilogram relationship atomic mass unit-kilogram relationship = 1.660 539 068 92 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v1
atomic unit of 1st hyperpolarizability atomic unit of 1st hyperpolarizability = 3.206 361 2996 × 10⁻⁵³ C³ m³ J⁻² (CODATA 2022 recommended value, NIST)	v1
atomic unit of 2nd hyperpolarizability atomic unit of 2nd hyperpolarizability = 6.235 379 9735 × 10⁻⁶⁵ C⁴ m⁴ J⁻³ (CODATA 2022 recommended value, NIST)	v1
atomic unit of action atomic unit of action = 1.054 571 817… × 10⁻³⁴ J s (CODATA 2022 recommended value, NIST)	v1
atomic unit of charge atomic unit of charge = 1.602 176 634 × 10⁻¹⁹ C (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: 69 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.