Mean Arterial Pressure and Pulse Pressure: Calculating Them From a Blood Pressure Reading
October 29, 2026
A blood pressure reading has two numbers: systolic (the pressure when the heart beats) over diastolic (the pressure between beats). Two other numbers can be derived from them. Pulse pressure is the difference: PP = SBP − DBP. Mean arterial pressure (MAP) is the average pressure during a cardiac cycle, which is closer to the diastolic value because the heart spends about two thirds of the cycle in diastole: MAP ≈ (SBP + 2 × DBP) ÷ 3.
For 120/80 mmHg, MAP = (120 + 160) ÷ 3 = 93.3 mmHg and PP = 40 mmHg.
Skip the math and get your answer instantly:
Open the BMI Calculator →Worked Examples
MAP estimates the perfusion pressure that drives blood to organs. Clinicians generally want a MAP of at least 65 mmHg to maintain organ perfusion, particularly in critical care. Pulse pressure reflects the stiffness of the arteries and the stroke volume; a wide pulse pressure (above 60) is associated with stiff arteries in older adults, while a narrow one (below 25% of the systolic value) may indicate low cardiac output. These values are screening numbers, and a clinician interprets them in context.
| Reading (SBP/DBP) | MAP (mmHg) | Pulse pressure (mmHg) |
|---|---|---|
| 90/60 | 70.0 | 30 |
| 120/80 | 93.3 | 40 |
| 140/90 | 106.7 | 50 |
| 160/100 | 120.0 | 60 |
American Heart Association Categories
Normal: below 120 systolic and below 80 diastolic. Elevated: 120 to 129 systolic and below 80 diastolic. Stage 1 hypertension: 130 to 139 systolic or 80 to 89 diastolic. Stage 2 hypertension: 140 or higher systolic or 90 or higher diastolic. Hypertensive crisis: above 180 systolic and/or above 120 diastolic, which needs prompt medical attention. Diagnosis requires repeated measurements on different occasions, not a single reading.
Getting an Accurate Reading
Sit quietly for 5 minutes with your back supported, feet flat, and arm at heart level. Use a correctly sized cuff. Avoid caffeine, exercise, and smoking for 30 minutes before. Take two readings a minute apart and record the average. Measure at the same time of day. Home monitors validated for accuracy are useful for tracking, and the results help your clinician.
Limits of the Formula
The MAP formula assumes a typical heart rate. At fast heart rates, systole takes up a bigger share of the cycle, and the weighting shifts, so the estimate becomes less accurate. Direct measurement in the hospital uses an arterial line. This article is educational and does not replace medical advice; if your readings are consistently high or you have symptoms such as chest pain, severe headache, or vision changes, seek care.
Frequently Asked Questions
How do I calculate mean arterial pressure?
MAP = (systolic + 2 × diastolic) ÷ 3.
What is pulse pressure?
The difference between systolic and diastolic pressure.
What MAP is considered adequate?
At least 65 mmHg for organ perfusion.
What is stage 2 hypertension?
140 or higher systolic or 90 or higher diastolic.
Can one reading diagnose hypertension?
No. Several readings over time are needed.