Constants

[Perillux]

Where can I see a list of the most up to date standards for constant values.

For example: google says the mass of an electron is 9.10938188x10^-31
while wikipedia says it is 9.10938215(45)x10^-31
other sources say 9.0195x10^-31

It is the same for many other constants as well

[atyy]

Try the Particle Data Group
http://pdg.lbl.gov/

[mathman]

http://physics.nist.gov/cuu/Constants/

Above is link u.s. govt standards

[Redbelly98]

Just to add to mathman's excellent link, those are the 2006 "CODATA Internationally recommended values of the Fundamental Physical Constants"

These get updated about every 20 years or so.