Find answers to these questions along with mapping out your conversion goals and conversion rate goals. How Do You Calculate Conversion Rate? Conversion Rate FormulaThe formula to calculate the conversion rate is straightforward:Conversions / Visits* = Conversion Rate*I have to include an asterisk, though, as some definitions might not be as straightforward. Why Do I Need To Be Able To Calculate Conversion Rate? Out of the box, Google has no context as to what a conversion is for you and no ability to calculate a conversion rate off of it.