I respectfully disagree with Sledneck. (am I allowed to do that??
The most often referenced composition, thus the standard, if you will, is 1 cup salt to 1 gallon water. The additional flavor and aromatic components, i.e. sugar, spices, garlic, syrup, etc. are added to that 1:1 base. It is the salt that works the magic and contributes a negligible amount of sodium to the finished product (if dietary concerns are an issue) if the technique is performed correctly, including rinsing the bird when the brining is complete.
But, if the end result of 1/2, 1/2 to gallon provides what you like, then that is good.