The ratio of HDL/LDL looks at the ratio of good cholesterol (HDL) to bad cholesterol (LDL). The ratio is determined by dividing the LDL cholesterol into the HDL cholesterol. For example, if a person has an HDL cholesterol of 50 mg/dL and an LDL cholesterol of 150 mg/dL, the HDL/LDL ratio would be 0.33. The goal is to keep the ratio above 0.3, with the ideal HDL/LDL ratio being above 0.4.