Why isn't standard Gibbs free energy always zero?

I read in my textbook that one of the standard conditions we should use when calculating the standard Gibbs free energy is having a concentration of 1 M of all the reagents and the products in the reaction. But if you use the formula $G = -RT\ln K\_\mathrm e$ and you use 1 M to calculate it, you would always get zero.


So that means 1 M would be the initial concentration of reagents and products before reaching equilibrium?




$\Delta G = \Delta G^\circ - RT \ln(K)$


It isn't directly $G$, but formula for change in free energy. Also, in standard conditions $\Delta G = \Delta G^\circ$, so it isn't necessarily 0.


[Relevant reading on a website](http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch21/gibbs.php)


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