Mean Arterial Pressure Calculator
MAP is an estimate based on a resting brachial blood pressure reading and is not medical advice. A MAP near 70-100 mmHg is generally considered adequate for organ perfusion, but interpretation depends on clinical context. Consult a healthcare professional.
Mean arterial pressure (MAP) is the average pressure pushing blood through your arteries across one full cardiac cycle, and it reflects how well blood reaches your organs. This calculator derives MAP from a standard cuff reading using MAP = DBP + (SBP - DBP) / 3, because the heart spends roughly two-thirds of each beat in diastole. It also reports pulse pressure and a broad category for quick context.
Formula
MAP = DBP + (SBP - DBP) / 3
- SBP
- Systolic blood pressure (mmHg)
- DBP
- Diastolic blood pressure (mmHg)
- MAP
- Mean arterial pressure (mmHg)
How it works
- Enter your systolic (top) and diastolic (bottom) blood pressure numbers in mmHg from a resting reading.
- The calculator finds pulse pressure (systolic minus diastolic), divides it by three, and adds it to diastolic to estimate MAP.
- It labels the MAP as Low (under 70), Normal (70-100), or Elevated (over 100) mmHg as a rough orientation only.
Worked example
A typical reading of 120/80 mmHg is converted to mean arterial pressure.
- Pulse pressure = 120 - 80 = 40 mmHg.
- One third of pulse pressure = 40 / 3 = 13.33 mmHg.
- MAP = 80 + 13.33 = 93.33, rounded to 93.3 mmHg.
A 120/80 reading gives a MAP of about 93.3 mmHg, which falls in the normal range.
Frequently asked questions
- Why is diastolic weighted more heavily in the MAP formula?
- At normal resting heart rates the heart spends roughly two-thirds of each cycle in diastole and one-third in systole. The formula MAP = DBP + (SBP - DBP) / 3 mirrors that timing, so diastolic pressure contributes more to the average.
- What is a healthy mean arterial pressure?
- A MAP of about 70 to 100 mmHg is generally considered sufficient to perfuse the vital organs in a resting adult. Values much below 60-65 mmHg may indicate inadequate perfusion, but interpretation always depends on the clinical situation.
- Is the divide-by-three formula exact?
- No. It is an approximation that holds best at typical resting heart rates. At very high heart rates diastole shortens, so the true average shifts toward systolic and the formula becomes less accurate.
- Can I use this for medical decisions?
- No. This calculator is for general education and is not medical advice or a diagnosis. Discuss your blood pressure and any MAP target with a qualified healthcare professional.