Information at the foundation of modern science and technology from the Physical Measurement Laboratory of NIST

		CODATA Internationally recommended 2022 values of the

Constants Topics: Values Energy Equivalents Searchable Bibliography Background Constants Bibliography Constants, Units & Uncertainty home page

Version history and disclaimer   (e.g., electron mass, most misspellings okay) Search by name    Display  alphabetical list,   table (image), or   table (pdf)      by clicking a category below Find the correlation coefficient between any pair of constants See also Publication: CODATA Recommended Values of the Fundamental Physical Constants: 2022 (PDF) Wall Chart and Wallet Card of the 2022 constants Background information related to the constants Links to selected scientific data Previous Values (2018) (2014) (2010) (2006) (2002) (1998) (1986) (1973) (1969) DEADLINE NOTICE The 2026 CODATA adjustment of the fundamental constants is the next regularly scheduled adjustment. Data being used in this adjustment is required to have been discussed in a publication preprint or a publication prior to 31 December 2026.

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