Universal Physical Constants

From http://physics.nist.gov/constants

Standardized values for universal physical constants are recommended and periodically updated by the Committee on Data for Science and Technology. They include electromagnetic, atomic, physical, chemical, and x-ray related constants, as well as conversion factors. They are related to certain mathematical constants, such as pi and the natural base, e.The constants listed in these tables were recommended in 2002 and renewed in 2004 by the Committee on Data for Science and Technology (CODATA). They replace the former set, published in 1998. This self-consistent set represents the current, internationally-recognized standard.