Pulse pressure is the difference between your systolic blood pressure (the top number) and your diastolic blood pressure (the bottom number). If your blood pressure reading is 120/80 mmHg, your pulse pressure is 120 minus 80, which equals 40 mmHg. A healthy pulse pressure generally falls around 40 mmHg, though anywhere from about 30 to 50 is considered normal for most adults.
The Formula
The calculation is straightforward:
Pulse pressure = Systolic BP − Diastolic BP
Both numbers come from a standard blood pressure reading and are measured in millimeters of mercury (mmHg). If your blood pressure is 135/85, your pulse pressure is 50 mmHg. If it’s 110/70, your pulse pressure is 40 mmHg. You don’t need any special equipment beyond a regular blood pressure monitor.
What Your Result Means
A pulse pressure around 40 mmHg is a useful benchmark, but the important thing is where your number falls relative to your systolic pressure. A pulse pressure above 60 mmHg is generally considered wide (high), while a narrow (low) pulse pressure is one that’s one-quarter or less of your systolic reading. For someone with a systolic pressure of 120, that threshold would be 30 mmHg or below.
Wide pulse pressure often reflects stiffened arteries. As arteries lose their elasticity, the systolic number climbs while diastolic stays the same or even drops, stretching the gap between them. Narrow pulse pressure, on the other hand, can signal that your heart isn’t pumping enough blood. This is seen in conditions like heart failure, and it also occurs with significant blood loss from trauma or internal bleeding.
Why Pulse Pressure Matters for Heart Health
Pulse pressure is more than a curiosity on a blood pressure report. Data from the Framingham Heart Study showed it to be a more powerful predictor of cardiovascular disease than either systolic or diastolic pressure alone. Research published in the journal Hypertension found that among people with high blood pressure, those with the widest pulse pressures faced the highest risk of coronary events across the full range of systolic readings. The effect was strongest when systolic pressure was already elevated.
Interestingly, the relationship between diastolic pressure and heart risk followed a J-shaped curve in that same analysis. Very low diastolic readings, when paired with high systolic readings, actually increased coronary risk. That pattern makes sense: a low diastolic number widens pulse pressure, and it’s the wide pulse pressure driving the danger. Stroke risk, by contrast, tracked more closely with overall mean blood pressure rather than pulse pressure specifically.
What Causes High Pulse Pressure
The most common driver is arterial stiffness, which progresses naturally with age. Over time, the walls of your large arteries thicken, lose elastic fibers, and accumulate collagen. These stiffer vessels can’t absorb the force of each heartbeat as well, so systolic pressure rises. The pressure wave also bounces back from the periphery faster in stiff arteries, adding to the systolic peak instead of cushioning it. This increases the workload on your heart and, over years, can cause the heart’s left ventricle to thicken in response.
Other contributors to a wide pulse pressure include an overactive thyroid, severe anemia, and aortic valve problems that allow blood to leak backward after each heartbeat. In all of these cases, the gap between the top and bottom blood pressure numbers grows because systolic pressure rises, diastolic pressure drops, or both.
What Causes Low Pulse Pressure
A narrow pulse pressure typically means the heart is generating less force with each beat. Heart failure is one of the most common causes: the weakened heart can’t push out a full volume of blood, so systolic pressure drops closer to diastolic. Cardiac tamponade, where fluid builds up around the heart and compresses it, produces a similar effect. Major blood loss from injury or internal bleeding also narrows pulse pressure because there’s simply less blood volume for the heart to move.
Getting an Accurate Blood Pressure Reading
Your pulse pressure calculation is only as good as the blood pressure numbers that go into it. Small errors in technique can shift your reading by several points in either direction, which is enough to change your pulse pressure meaningfully.
Sit quietly for at least five minutes before measuring. Your feet should be flat on the floor, your back supported, and your right arm resting on a table at heart level, roughly halfway between your shoulders and waist. If you’re tall, prop your arm on a pillow or thick book so the cuff isn’t sitting below your ribcage. If you’re shorter, use a cushion on the chair to raise yourself and a box under your feet if they don’t reach the floor.
Avoid coffee, alcohol, and cigarettes for at least 30 minutes before measuring, as all three can temporarily alter your reading. Take multiple readings, waiting at least one minute between each, and use the average. Home monitors are convenient, but make sure you’re using a cuff that fits your arm. A cuff that’s too small will artificially inflate your numbers.
How Exercise Affects Pulse Pressure
During vigorous activity, systolic pressure rises sharply while diastolic pressure stays roughly the same or drops slightly, so pulse pressure widens temporarily. This is a normal response. What’s more interesting is what happens over time with regular training.
A study in Frontiers in Physiology found that postmenopausal women who completed 12 weeks of aerobic exercise training saw their aortic pulse pressure drop after a moderate cycling session, an effect that wasn’t present before they started the training program. In other words, the same intensity of exercise produced a healthier pulse pressure response once their cardiovascular fitness improved. Similar reductions have been observed in young healthy men after moderate-intensity exercise. The post-exercise drop in pulse pressure was temporary, fading within about 60 minutes, but repeated over months of training, these acute improvements reflect real changes in arterial flexibility.
Regular aerobic exercise is one of the few interventions that can meaningfully reduce arterial stiffness, which makes it one of the most effective ways to keep your pulse pressure in a healthy range as you age.