A normal blood pressure reading is 120/80 mmHg and lesser. A healthy young woman's normal blood pressure is lower than 120 mmHg systolic and 80 mmHg diastolic and can range from 90/60 mmHg to 120/80 mmHg. High blood pressure is a blood pressure of 140/90 mmHg or higher. When systolic and diastolic blood pressures differ in categories, the greater category is used to classify blood pressure levels.