For most people, pulse and heart rate are the same number, and the terms are often used interchangeably. But they measure two different things. Your heart rate is the number of times your heart squeezes per minute. Your pulse is the number of times your arteries expand and contract in response to that squeezing. In a healthy person, these numbers match. In certain medical conditions, they don’t.
How Heart Rate and Pulse Work Differently
Each heartbeat starts as an electrical signal that tells the heart muscle to contract. That contraction pushes blood out of the left ventricle and into the aorta, creating a pressure wave that ripples outward through your arterial system. By the time that wave reaches your wrist or neck, you can feel it as a pulse. So heart rate is the electrical and mechanical event at the heart itself, while pulse is the downstream result you detect in your arteries.
Think of it like dropping a stone into water. The stone hitting the surface is the heartbeat. The ripple that reaches the shore is the pulse. Usually there’s one ripple for every stone. But if the stone is too small, or the water conditions are off, the ripple might not make it to shore at all.
When the Two Numbers Don’t Match
The gap between heart rate and pulse is called a pulse deficit. It happens when the heart contracts but doesn’t generate enough pressure to push blood all the way through the arteries. The heart needs to build roughly 60 to 80 mm Hg of pressure to force open the aortic valve and send blood into circulation. If a beat is too weak or comes too early, the valve doesn’t open fully, and no pulse wave reaches your wrist, even though the heart did contract.
The most common cause is atrial fibrillation, a condition where the heart’s upper chambers quiver erratically instead of contracting in a coordinated rhythm. Some of those chaotic beats don’t fill the ventricle with enough blood to produce a detectable pulse. Premature ventricular contractions (extra beats that come too early) can do the same thing. Severe low blood pressure or significant blood loss can also cause a pulse deficit, because the overall pressure in the system is too low for every beat to register at the wrist.
To check for a pulse deficit, a clinician listens to the heart directly with a stethoscope (the apical pulse) while simultaneously feeling the pulse at the wrist. If the two counts don’t match over one minute, the difference is the deficit. A pulse deficit is a red flag that something is disrupting the heart’s ability to pump effectively.
Where You Can Feel Your Pulse
You can detect a pulse anywhere an artery runs close to the surface and over a bone. The most commonly used spots are:
- Radial artery (wrist): just above the wrist joint near the base of your thumb. This is the standard self-check location.
- Carotid artery (neck): on either side of the neck, below the jaw and to the side of the windpipe. Often used during exercise or emergencies because it’s easy to find.
- Dorsalis pedis (foot): on the top of the foot in the groove between the first and second toes. Clinicians check this to assess circulation in the lower extremities.
Press gently with your index and middle fingers. Don’t use your thumb, which has its own pulse and can cause a miscount.
What Your Pulse Can Tell You Beyond the Count
Pulse isn’t just a number. It also has qualities that reveal information about your cardiovascular health. Clinicians assess pulse strength on a four-point scale: 0 means no detectable pulse, 1+ is weak and thready, 2+ is normal, and 3+ is full and bounding.
A weak, thready pulse can signal that the heart isn’t pumping enough blood with each beat. This shows up in conditions like heart failure, heat exhaustion, or significant blood loss. A bounding pulse, where each beat feels exaggerated under your fingers, can result from exercise or stress, but also from fluid overload or high blood pressure. Your pulse also has rhythm. A steady, evenly spaced pulse suggests a regular heart rhythm. Irregular spacing between beats could point to arrhythmias worth investigating.
Normal Resting Numbers
A normal resting heart rate for adults falls between 60 and 100 beats per minute. Well-trained athletes often have resting rates closer to 40 beats per minute, because their hearts pump more blood with each contraction and don’t need to beat as often. If you’re not an athlete and your resting rate consistently falls below 60 or above 100, it’s worth paying attention to how you feel. Dizziness, fatigue, or shortness of breath alongside an unusual rate is more meaningful than the number alone.
What Your Smartwatch Actually Measures
Most wearable devices use optical sensors that shine light through your skin and detect changes in blood volume in your capillaries. This is a pulse measurement, not a true heart rate measurement. The device is reading pressure changes in your arteries, not your heart’s electrical signals. For the majority of people, the result is the same number you’d get from a heart rate reading, so the distinction is academic.
It matters, though, if you have an irregular heart rhythm. A wrist-based optical sensor can miss beats that don’t produce enough blood flow to register, giving you an artificially low reading. Only devices equipped with electrocardiogram (EKG) technology actually detect the electrical impulses that trigger each heartbeat. Some newer smartwatches include this feature, but you typically have to activate it manually rather than relying on continuous background monitoring.
If you’re tracking your heart health with a wearable and notice consistently irregular readings or numbers that don’t match how you feel, the device may be picking up on a real discrepancy between your pulse and your actual heart rate.