Fundamental Physical Constants from NIST
The NIST Reference on Constants, Units and Uncertainty Information at the foundation of modern science and technology from the Physical Measurement Laboratory of NIST

CODATA Internationally recommended 2022 values of the
Fundamental Physical Constants

Constants
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Values
Energy
Equivalents
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Constants
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  (e.g., electron mass, most misspellings okay)
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    Find the correlation coefficient between any pair of constants

    See also
    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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NIST Standard Reference Database 121. Last Update to Data Content: May 2024.
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Online: October 1994   -   Last update: May 2024