Mean Arterial Pressure (MAP) Calculator
What is Mean Arterial Pressure (MAP) Calculator
Mean arterial pressure (MAP) is the average pressure in the arteries during one heartbeat, and it reflects how well the organs are being perfused. It is estimated from a blood pressure reading with the formula MAP = (systolic + 2 times diastolic) divided by 3. Diastole is weighted twice because the heart spends about two-thirds of each cycle in diastole. A MAP around 70 to 100 mmHg is typical.
How to use
- Enter the systolic pressure in mmHg (the top number).
- Enter the diastolic pressure in mmHg (the bottom number).
- Read the MAP in mmHg and its reference band.
- Check the pulse pressure shown below the result.
When to use it
Have a reading of 120/80 and want the MAP? Enter both and you get 93 mmHg, in the normal band, with a pulse pressure of 40. It is the number to watch when a systolic or diastolic value alone does not tell you whether perfusion is adequate.
Frequently asked questions
What is the formula for mean arterial pressure?
MAP = (systolic + 2 × diastolic) ÷ 3. For a reading of 120/80, that is (120 + 160) ÷ 3 = 93 mmHg. An equivalent form is diastolic + (systolic − diastolic) ÷ 3.
Why is diastolic counted twice?
At normal heart rates the heart spends roughly twice as long in diastole as in systole, so diastolic pressure contributes about two-thirds of the average. That is why it is weighted twice in the estimate.
What is a good MAP?
A MAP of about 70 to 100 mmHg is typical. A value of roughly 65 mmHg or more is often used as a minimum perfusion target for the organs, but the right target depends on the patient and the clinical situation.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button — anyone who opens the link will see your exact inputs ready to go.
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