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 241–264 of 355 documents

Document	Version
neutron relative atomic mass neutron relative atomic mass = 1.008 664 916 06 (CODATA 2022 recommended value, NIST)	v1
neutron to shielded proton mag. mom. ratio neutron to shielded proton mag. mom. ratio = -0.684 996 94 (CODATA 2022 recommended value, NIST)	v2
neutron-electron mag. mom. ratio neutron-electron mag. mom. ratio = 1.040 668 84 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
neutron-electron mass ratio neutron-electron mass ratio = 1838.683 662 00 (CODATA 2022 recommended value, NIST)	v1
neutron-muon mass ratio neutron-muon mass ratio = 8.892 484 08 (CODATA 2022 recommended value, NIST)	v1
neutron-proton mag. mom. ratio neutron-proton mag. mom. ratio = -0.684 979 35 (CODATA 2022 recommended value, NIST)	v2
neutron-proton mass difference neutron-proton mass difference = 2.305 574 61 × 10⁻³⁰ kg (CODATA 2022 recommended value, NIST)	v1
neutron-proton mass difference energy equivalent neutron-proton mass difference energy equivalent = 2.072 147 12 × 10⁻¹³ J (CODATA 2022 recommended value, NIST)	v1
neutron-proton mass difference energy equivalent in MeV neutron-proton mass difference energy equivalent in MeV = 1.293 332 51 MeV (CODATA 2022 recommended value, NIST)	v1
neutron-proton mass difference in u neutron-proton mass difference in u = 1.388 449 48 × 10⁻³ u (CODATA 2022 recommended value, NIST)	v1
neutron-proton mass ratio neutron-proton mass ratio = 1.001 378 419 46 (CODATA 2022 recommended value, NIST)	v1
neutron-tau mass ratio neutron-tau mass ratio = 0.528 779 (CODATA 2022 recommended value, NIST)	v1
Newtonian constant of gravitation Newtonian constant of gravitation = 6.674 30 × 10⁻¹¹ m³ kg⁻¹ s⁻² (CODATA 2022 recommended value, NIST)	v2
Newtonian constant of gravitation over h-bar c Newtonian constant of gravitation over h-bar c = 6.708 83 × 10⁻³⁹ (GeV/c²)⁻² (CODATA 2022 recommended value, NIST)	v1
nuclear magneton nuclear magneton = 5.050 783 7393 × 10⁻²⁷ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
nuclear magneton in eV/T nuclear magneton in eV/T = 3.152 451 254 17 × 10⁻⁸ eV T⁻¹ (CODATA 2022 recommended value, NIST)	v1
nuclear magneton in inverse meter per tesla nuclear magneton in inverse meter per tesla = 2.542 623 410 09 × 10⁻² m⁻¹ T⁻¹ (CODATA 2022 recommended value, NIST)	v1
nuclear magneton in K/T nuclear magneton in K/T = 3.658 267 7706 × 10⁻⁴ K T⁻¹ (CODATA 2022 recommended value, NIST)	v1
nuclear magneton in MHz/T nuclear magneton in MHz/T = 7.622 593 2188 MHz T⁻¹ (CODATA 2022 recommended value, NIST)	v1
Planck constant Planck constant = 6.626 070 15 × 10⁻³⁴ J Hz⁻¹ (CODATA 2022 recommended value, NIST)	v2
Planck constant in eV/Hz Planck constant in eV/Hz = 4.135 667 696… × 10⁻¹⁵ eV Hz⁻¹ (CODATA 2022 recommended value, NIST)	v1
Planck length Planck length = 1.616 255 × 10⁻³⁵ m (CODATA 2022 recommended value, NIST)	v1
Planck mass Planck mass = 2.176 434 × 10⁻⁸ kg (CODATA 2022 recommended value, NIST)	v1
Planck mass energy equivalent in GeV Planck mass energy equivalent in GeV = 1.220 890 × 10¹⁹ GeV (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.