About the Pulse Pressure Calculator
Pulse pressure is the difference between systolic (top number) and diastolic (bottom number) blood pressure. A reading of 120/80 mmHg has a pulse pressure of 40 mmHg. This calculator works it out from any reading and adds two related figures: the mean arterial pressure (MAP) and pulse pressure as a percentage of systolic pressure, which is how a narrow pulse pressure is usually judged.
It is useful for students learning haemodynamics, nurses and clinicians reviewing observations, and anyone curious about a home blood pressure reading. A pulse pressure persistently above about 60 mmHg in an older adult usually reflects stiffening of the large arteries, and in the Framingham Heart Study a higher pulse pressure was linked to higher coronary heart disease risk in people aged 50–79. A very narrow pulse pressure (below roughly a quarter of systolic) can accompany low stroke volume, such as in blood loss, heart failure, aortic stenosis or cardiac tamponade.
The thresholds used here are common teaching cut-offs, not diagnostic criteria. Pulse pressure should always be read alongside the full blood pressure, heart rate and the clinical picture.
With the default inputs, the pulse pressure is 40 mmHg. Change any value above to recalculate instantly.
How to use the pulse pressure calculator
- 1Take a seated blood pressure reading after five minutes of rest.
- 2Enter the systolic (top) number.
- 3Enter the diastolic (bottom) number.
- 4Read the pulse pressure and whether it is narrow, typical or wide.
- 5Check the MAP and the pulse pressure percentage for context.
Formula and method
Pulse pressure is simply systolic minus diastolic pressure. It is determined mainly by the volume of blood the heart ejects with each beat (stroke volume) and by how stiff the aorta and large arteries are: stiffer arteries cannot absorb the pulse, so systolic rises and diastolic falls, widening the gap.
Mean arterial pressure is estimated with the standard bedside approximation (diastolic plus one third of pulse pressure), which assumes a normal heart rate where diastole lasts about two thirds of the cardiac cycle. A pulse pressure under 25% of systolic is used as the usual definition of a narrow pulse pressure; above 60 mmHg is a common definition of a wide one.
- PP
- Pulse pressure (mmHg)
- SBP
- Systolic blood pressure (mmHg)
- DBP
- Diastolic blood pressure (mmHg)
- MAP
- Mean arterial pressure (mmHg)
Worked examples
Textbook reading of 120/80
120 − 80 = 40 mmHg, which is one third (33.3%) of the systolic pressure. MAP is 80 + 40 ÷ 3 = 93.3 mmHg.
Older adult with isolated systolic hypertension, 165/75
165 − 75 = 90 mmHg, well above the 60 mmHg threshold for a wide pulse pressure, typical of arterial stiffening. MAP is 75 + 30 = 105 mmHg.
Narrow pulse pressure, 92/76
92 − 76 = 16 mmHg, only 17.4% of systolic — below the 25% cut-off for a narrow pulse pressure, which can accompany a low stroke volume.
Frequently asked questions
What is a normal pulse pressure?+
For a healthy adult at rest it is usually around 40 mmHg (for example 120/80). Values roughly between 30 and 60 mmHg are common; pulse pressure tends to rise with age as arteries stiffen.
What does a wide pulse pressure mean?+
A pulse pressure above about 60 mmHg is called wide. In older adults it mostly reflects stiffening of the aorta and is associated with higher cardiovascular risk. Other causes include aortic regurgitation, severe anaemia, fever, pregnancy and an overactive thyroid.
What does a narrow pulse pressure mean?+
A pulse pressure below about 25% of systolic pressure is called narrow. It suggests the heart is ejecting a small volume per beat, as can happen with significant blood loss, heart failure, aortic stenosis or cardiac tamponade.
Is pulse pressure the same as pulse rate?+
No. Pulse rate (heart rate) is the number of beats per minute. Pulse pressure is the difference between the systolic and diastolic blood pressure, measured in mmHg.
Can pulse pressure predict heart disease?+
In the Framingham Heart Study of adults aged 50–79, pulse pressure was at least as good as systolic or diastolic pressure alone at predicting coronary heart disease, and risk rose as pulse pressure widened. It is a risk marker, not a diagnosis.
For healthcare professionals and education only. This calculator implements a published formula or score but is not a diagnosis and does not replace clinical judgment. Verify inputs and results against the original source before using them in patient care.