The mean arterial pressure calculator computes MAP from systolic and diastolic blood pressure readings using the standard formula: MAP = (Systolic + 2 × Diastolic) ÷ 3. MAP is the average pressure in the arterial circulation throughout the cardiac cycle and is the key haemodynamic parameter used to assess adequate organ perfusion. A MAP of at least 60–65 mmHg is required to perfuse the brain, kidneys, and coronary arteries; in septic shock, a target MAP of ≥65 mmHg is a core resuscitation endpoint.
| MAP Value | Interpretation |
|---|---|
| < 60 mmHg | Critical — inadequate organ perfusion (shock) |
| 60–69 mmHg | Low — monitor closely, intervene if symptomatic |
| 70–100 mmHg | Normal — adequate organ perfusion |
| 101–110 mmHg | Elevated — hypertension, monitor |
| > 110 mmHg | Severely elevated — assess for hypertensive urgency/emergency |
Calculated as MAP = (systolic + 2 × diastolic) ÷ 3. The diastolic is weighted twice because the heart spends roughly two-thirds of each cycle in diastole — which is also why a low diastolic pulls the MAP down faster than people expect.
| Blood pressure | MAP | Interpretation |
|---|---|---|
| 120/80 | 93 mmHg | Normal |
| 110/70 | 83 mmHg | Normal |
| 100/60 | 73 mmHg | Adequate perfusion |
| 90/60 | 70 mmHg | Borderline — monitor closely |
| 90/50 | 63 mmHg | Below target — organ perfusion at risk |
| 85/45 | 58 mmHg | Low — intervention usually needed |
| 140/90 | 107 mmHg | Elevated |
| 160/100 | 120 mmHg | High |
The number most often quoted as the floor is 65 mmHg — the MAP generally considered the minimum needed to perfuse the brain, kidneys, and other organs, and the usual target in sepsis and shock resuscitation. Look at the 90/50 row: the systolic still reads 90, which can look acceptable at a glance, yet the MAP has dropped to 63. That gap is exactly why MAP is worth calculating rather than eyeballing the top number.
Normal MAP is 70–100 mmHg. A MAP below 60 mmHg is considered critically low and indicates inadequate perfusion of vital organs. In clinical practice, a MAP of ≥65 mmHg is the standard target in patients with septic shock receiving vasopressors.
MAP is not simply the average of systolic and diastolic — it is a weighted average that accounts for the fact that the heart spends approximately twice as long in diastole as in systole at normal heart rates. The formula MAP = (SBP + 2 × DBP) ÷ 3 reflects this weighting.
Below 65 mmHg is generally the point at which organ perfusion is at risk, and 65 is the usual resuscitation target in sepsis and shock. Patients with chronic hypertension may need a higher MAP to perfuse adequately, so targets are set individually.
93 mmHg. Using (systolic + 2 × diastolic) ÷ 3: (120 + 160) ÷ 3 = 93 mmHg, comfortably within the normal range of roughly 70–100 mmHg.