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 265–288 of 355 documents

Document	Version
Planck temperature Planck temperature = 1.416 784 × 10³² K (CODATA 2022 recommended value, NIST)	v1
Planck time Planck time = 5.391 247 × 10⁻⁴⁴ s (CODATA 2022 recommended value, NIST)	v1
proton charge to mass quotient proton charge to mass quotient = 9.578 833 1430 × 10⁷ C kg⁻¹ (CODATA 2022 recommended value, NIST)	v2
proton Compton wavelength proton Compton wavelength = 1.321 409 853 60 × 10⁻¹⁵ m (CODATA 2022 recommended value, NIST)	v1
proton g factor proton g factor = 5.585 694 6893 (CODATA 2022 recommended value, NIST)	v1
proton gyromag. ratio proton gyromag. ratio = 2.675 221 8708 × 10⁸ s⁻¹ T⁻¹ (CODATA 2022 recommended value, NIST)	v2
proton gyromag. ratio in MHz/T proton gyromag. ratio in MHz/T = 42.577 478 461 MHz T⁻¹ (CODATA 2022 recommended value, NIST)	v2
proton mag. mom. proton mag. mom. = 1.410 606 795 45 × 10⁻²⁶ J T⁻¹ (CODATA 2022 recommended value, NIST)	v2
proton mag. mom. to Bohr magneton ratio proton mag. mom. to Bohr magneton ratio = 1.521 032 202 30 × 10⁻³ (CODATA 2022 recommended value, NIST)	v2
proton mag. mom. to nuclear magneton ratio proton mag. mom. to nuclear magneton ratio = 2.792 847 344 63 (CODATA 2022 recommended value, NIST)	v2
proton mag. shielding correction proton mag. shielding correction = 2.567 15 × 10⁻⁵ (CODATA 2022 recommended value, NIST)	v2
proton mass proton mass = 1.672 621 925 95 × 10⁻²⁷ kg (CODATA 2022 recommended value, NIST)	v2
proton mass energy equivalent proton mass energy equivalent = 1.503 277 618 02 × 10⁻¹⁰ J (CODATA 2022 recommended value, NIST)	v1
proton mass energy equivalent in MeV proton mass energy equivalent in MeV = 938.272 089 43 MeV (CODATA 2022 recommended value, NIST)	v1
proton mass in u proton mass in u = 1.007 276 466 5789 u (CODATA 2022 recommended value, NIST)	v1
proton molar mass proton molar mass = 1.007 276 467 64 × 10⁻³ kg mol⁻¹ (CODATA 2022 recommended value, NIST)	v1
proton relative atomic mass proton relative atomic mass = 1.007 276 466 5789 (CODATA 2022 recommended value, NIST)	v1
proton rms charge radius proton rms charge radius = 8.4075 × 10⁻¹⁶ m (CODATA 2022 recommended value, NIST)	v2
proton-electron mass ratio proton-electron mass ratio = 1836.152 673 426 (CODATA 2022 recommended value, NIST)	v1
proton-muon mass ratio proton-muon mass ratio = 8.880 243 38 (CODATA 2022 recommended value, NIST)	v1
proton-neutron mag. mom. ratio proton-neutron mag. mom. ratio = -1.459 898 02 (CODATA 2022 recommended value, NIST)	v2
proton-neutron mass ratio proton-neutron mass ratio = 0.998 623 477 97 (CODATA 2022 recommended value, NIST)	v1
proton-tau mass ratio proton-tau mass ratio = 0.528 051 (CODATA 2022 recommended value, NIST)	v1
quantum of circulation quantum of circulation = 3.636 947 5467 × 10⁻⁴ m² s⁻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.