We recently released a simple tool to help you make smarter decisions about how much you should spend on online advertising.
The tool asks for four pieces of information: your conversion rate, average order size, gross margin, and other expenses. It then calculates a break-even CPC, CPA, and MER. Do not worry if you do not understand all of these terms because they are all defined and explained below the calculator.
You can access the tool for free here.