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 217–240 of 355 documents

Document	Version
muon-proton mass ratio muon-proton mass ratio = 0.112 609 5262 (CODATA 2022 recommended value, NIST)	v1
muon-tau mass ratio muon-tau mass ratio = 5.946 35 × 10⁻² (CODATA 2022 recommended value, NIST)	v1
natural unit of action natural unit of action = 1.054 571 817… × 10⁻³⁴ J s (CODATA 2022 recommended value, NIST)	v1
natural unit of action in eV s natural unit of action in eV s = 6.582 119 569… × 10⁻¹⁶ eV s (CODATA 2022 recommended value, NIST)	v1
natural unit of energy natural unit of energy = 8.187 105 7880 × 10⁻¹⁴ J (CODATA 2022 recommended value, NIST)	v1
natural unit of energy in MeV natural unit of energy in MeV = 0.510 998 950 69 MeV (CODATA 2022 recommended value, NIST)	v1
natural unit of length natural unit of length = 3.861 592 6744 × 10⁻¹³ m (CODATA 2022 recommended value, NIST)	v1
natural unit of mass natural unit of mass = 9.109 383 7139 × 10⁻³¹ kg (CODATA 2022 recommended value, NIST)	v1
natural unit of momentum natural unit of momentum = 2.730 924 534 46 × 10⁻²² kg m s⁻¹ (CODATA 2022 recommended value, NIST)	v1
natural unit of momentum in MeV/c natural unit of momentum in MeV/c = 0.510 998 950 69 MeV/c (CODATA 2022 recommended value, NIST)	v1
natural unit of time natural unit of time = 1.288 088 666 44 × 10⁻²¹ s (CODATA 2022 recommended value, NIST)	v1
natural unit of velocity natural unit of velocity = 299 792 458 m s⁻¹ (CODATA 2022 recommended value, NIST)	v1
neutron Compton wavelength neutron Compton wavelength = 1.319 590 903 82 × 10⁻¹⁵ m (CODATA 2022 recommended value, NIST)	v1
neutron g factor neutron g factor = -3.826 085 52 (CODATA 2022 recommended value, NIST)	v1
neutron gyromag. ratio neutron gyromag. ratio = 1.832 471 74 × 10⁸ s⁻¹ T⁻¹ (CODATA 2022 recommended value, NIST)	v2
neutron gyromag. ratio in MHz/T neutron gyromag. ratio in MHz/T = 29.164 6935 MHz T⁻¹ (CODATA 2022 recommended value, NIST)	v2
neutron mag. mom. neutron mag. mom. = -9.662 3653 × 10⁻²⁷ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
neutron mag. mom. to Bohr magneton ratio neutron mag. mom. to Bohr magneton ratio = -1.041 875 65 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
neutron mag. mom. to nuclear magneton ratio neutron mag. mom. to nuclear magneton ratio = -1.913 042 76 (CODATA 2022 recommended value, NIST)	v2
neutron mass neutron mass = 1.674 927 500 56 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v2
neutron mass energy equivalent neutron mass energy equivalent = 1.505 349 765 14 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
neutron mass energy equivalent in MeV neutron mass energy equivalent in MeV = 939.565 421 94 MeV (CODATA 2022 recommended value, NIST)	v1
neutron mass in u neutron mass in u = 1.008 664 916 06 u (CODATA 2022 recommended value, NIST)	v1
neutron molar mass neutron molar mass = 1.008 664 917 12 × 10⁻³ kg mol⁻¹ (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.