While searching the internet for information on how to install granite in my kitchen, I came across this site. They sell brackets for installing granite counter tops. They have a calculator tool that is amazing and very easy to use. All you need is the length and width of your granite and the tool calculates how many brackets you need.Here's the link

http://buygranitebrackets.com/granite-countertop-and-bracket-calculation-tools/granite-bracket-calculator/