(2) 120/80 mm Hg Explanation: According to the American Heart Association (AHA), normal blood pressure is a systolic pressure of less than 120 millimeters of mercury (mm Hg) and a diastolic pressure of less than 80 mm Hg, or 120/80 mm Hg. Having a blood pressure greater than 140/ 90 mm Hg is considered high blood pressure or hypertension.