Blood Pressure Calculator — MAP & pulse pressure

How it works

A blood-pressure reading gives two numbers — systolic (the peak, when the heart beats) over diastolic (the trough, when it rests). Two quantities are derived from them (StatPearls):

Mean arterial pressure (MAP) = diastolic + (systolic − diastolic) ÷ 3

Pulse pressure (PP) = systolic − diastolic

MAP approximates the average pressure in your arteries across the whole heartbeat. Because the heart spends more of each cycle in diastole, MAP is weighted toward the diastolic value rather than a simple midpoint. It matters clinically because organs need a MAP of roughly 60 mmHg or more to be adequately perfused with blood.

Pulse pressure is the gap between the two readings. A widening pulse pressure (often above ~60 mmHg) can reflect stiffening of the large arteries with age, while a very narrow one can accompany low stroke volume. Both numbers add context that the raw systolic/diastolic pair alone doesn't show.

Worked example

For a 120/80 reading:

• MAP = 80 + (120 − 80) ÷ 3 = 80 + 40 ÷ 3 = 80 + 13.3 ≈ 93.3 mmHg
• Pulse pressure = 120 − 80 = 40 mmHg

A 140/90 reading gives MAP ≈ 106.7 and pulse pressure 50; a 90/60 reading gives MAP 70 and pulse pressure 30.

Frequently asked questions

What is mean arterial pressure?

MAP is the average pressure in your arteries during one cardiac cycle. It is estimated as diastolic pressure plus one-third of the pulse pressure, and it reflects how well blood is being pushed to your organs.

Why is MAP not just the average of systolic and diastolic?

Because the heart spends about two-thirds of each cycle in diastole. Weighting toward the diastolic value — diastolic + ⅓(systolic − diastolic) — estimates the true average better than a simple midpoint.

What is pulse pressure?

Pulse pressure is the difference between systolic and diastolic pressure (systolic − diastolic). It reflects the force each heartbeat generates and the stiffness of the large arteries.

What is a healthy MAP?

A MAP of roughly 70–100 mmHg is typical, and at least about 60 mmHg is generally needed to perfuse vital organs. Values are interpreted in clinical context, not from one reading alone.

Is a single reading enough to know my blood pressure?

No. Blood pressure varies through the day and with activity and stress. Diagnosis relies on multiple readings over time, taken properly, and interpreted by a healthcare professional.

What do these numbers not tell me?

They don't classify your blood pressure or diagnose hypertension — that uses the systolic/diastolic values against clinical guidelines. MAP and pulse pressure add physiological context; they are not a substitute for medical evaluation.