Mean Arterial Pressure Calculator
Turn a blood-pressure reading into mean arterial pressure and pulse pressure — the figures clinicians use for organ perfusion and arterial stiffness.
The average pressure in your arteries over a heartbeat, from systolic and diastolic.
How the mean arterial pressure calculator works
A blood-pressure reading gives the peak (systolic) and trough (diastolic) of each heartbeat. Mean arterial pressure is the time-weighted average, and because the heart spends longer in diastole it is not the midpoint: MAP ≈ diastolic + ⅓ × (systolic − diastolic). Clinicians watch it because organs are perfused by the mean, and about 60–65 mmHg is usually cited as the minimum to keep them supplied.
Pulse pressure is simply systolic minus diastolic. It widens with stiffer arteries and age, which is why it is tracked alongside the two readings.
Formula: MAP = DBP + (SBP − DBP) ÷ 3 · pulse pressure = SBP − DBP
Worked examples
| Inputs | Mean arterial pressure | Note |
|---|---|---|
| 120 / 80 | 93.3 mmHg | the textbook reading |
| 140 / 90 | 106.7 mmHg | MAP 106.7 |
| 95 / 60 | 71.7 mmHg | MAP 71.7 |
FAQFrequently asked questions
Why is MAP not the average of the two numbers?
Because diastole lasts about twice as long as systole at a resting heart rate, so the pressure sits nearer the diastolic value for most of each beat. The ⅓ rule weights it accordingly.
What is a normal mean arterial pressure?
Around 70–100 mmHg for adults; 60–65 mmHg is widely cited as the floor needed to perfuse organs. It is a monitoring figure, not a diagnosis.
What does pulse pressure tell me?
The difference between systolic and diastolic. About 40 mmHg is typical; it widens with age as arteries stiffen, and a persistently wide pulse pressure is something doctors watch.
Does this calculator classify my blood pressure?
No — thresholds for hypertension differ between guidelines and countries. It converts a reading into MAP and pulse pressure; interpretation is for your doctor.
Where these figures come from
- Mifflin MD et al., "A new predictive equation for resting energy expenditure in healthy individuals", Am J Clin Nutr 1990 — the BMR equation used here
- World Health Organization — Waist circumference and waist–hip ratio (2008 expert consultation) — waist-to-hip cut-offs
- Tanaka H, Monahan KD, Seals DR, "Age-predicted maximal heart rate revisited", J Am Coll Cardiol 2001 — 208 − 0.7 × age
- Nathan DM et al., "Translating the A1C assay into estimated average glucose values" (ADAG), Diabetes Care 2008 — eAG = 28.7 × A1c − 46.7
- Mosteller RD, "Simplified calculation of body-surface area", N Engl J Med 1987 — BSA = √(height × weight / 3600)
- Centers for Disease Control and Prevention — national health guidance
Last checked: September 2026. The equations are fixed by their published papers and do not change with tax years or regulations; the thresholds quoted in verdicts name the body that set them.