High blood pressure is diagnosed by measuring a person’s blood pressure. There are multiple methods for measuring blood pressure, including using hand-powered cuffs and a stethoscope, semiautomatic monitors (either at the doctor’s office or at home), or ambulatory blood pressure monitors (which collect blood pressure readings several times per hour across a 24-hour period).
Broadly speaking, a systolic and diastolic blood pressure of <120 and <80 mmHg is considered optimal.[1] Hypertension is diagnosed at the doctor’s office if they measure a systolic and/or diastolic blood pressure of ≥ 130 and ≥ 80 mmHg over multiple measurements.