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CODATA Recommended Values of the Fundamental Physical Constants: 2014



Peter J. Mohr, David B. Newell, Barry N. Taylor


This paper gives the 2014 self-consistent set of values of the constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA). These values are based on a least-squares adjustment that takes into account all data available up to 31 December 2014. Details of the data selection and methodology of the adjustment are described. The recommended values may also be found on the World Wide Web at
J. Phys. & Chem. Ref. Data (JPCRD) -


fundamental constants, least-squares adjustment, CODATA recommended values, 2014 LSA


Mohr, P. , Newell, D. and Taylor, B. (2016), CODATA Recommended Values of the Fundamental Physical Constants: 2014, J. Phys. & Chem. Ref. Data (JPCRD), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 14, 2024)
Created November 22, 2016, Updated November 14, 2018