The brachial artery runs along the inner side of your upper arm, and the easiest way to find it is to feel for a pulse on the inside of your elbow crease, slightly toward the pinky side of the arm. It sits relatively close to the surface there, which is exactly why clinicians use that spot to listen for blood pressure sounds and draw arterial blood. But “slightly toward the pinky side” is vaguer than most people want, and the artery’s exact position shifts depending on your build, your arm’s angle, and whether your anatomy follows the textbook pattern. Here is how to locate it reliably and what to know once you do.
Where the Artery Sits and How It Travels
The brachial artery is the main blood supply to your upper arm. It begins near your armpit, where it continues from the axillary artery, and runs down the inner (medial) side of your arm alongside the humerus bone. As it descends, it gradually shifts from the inner edge of the biceps toward the front of the elbow. By the time it reaches the crease of your elbow, called the cubital fossa, the artery sits between the biceps tendon on the outer side and a bony bump on the inner side of your elbow called the medial epicondyle. Just below that crease, it splits into the two arteries that supply your forearm: the radial artery (the one you feel at your wrist on the thumb side) and the ulnar artery.
The artery does not travel alone. It runs in a bundle with the median nerve and brachial veins, and these structures can sometimes weave around each other in ways that matter for medical procedures. In some individuals, the median nerve crosses over or under the artery partway down the arm, and the brachial veins may drain into nearby veins in unusual patterns, creating a more complicated arrangement than anatomy diagrams suggest.1PubMed Central. Triple Independent Segmental Drainage of the Brachial Veins Into the Basilic Vein Associated With Variant Formation of the Median Nerve: A Cadaveric Case Report
Feeling for the Brachial Pulse Step by Step
You will need a relaxed arm and two or three fingertips. Here is how to do it:
- Position the arm: Extend the arm you want to check, palm facing upward, with a slight bend at the elbow. Resting the arm on a flat surface or armrest helps keep the muscles relaxed, which makes the pulse easier to feel.
- Find the landmark: Look at the inside of your elbow. You should see or feel the biceps tendon, which is the firm cord running down the center of the crease. The brachial artery sits just to the medial (inner) side of that tendon.
- Apply gentle pressure: Place the pads of your index and middle fingers (not your thumb, which has its own pulse and can confuse you) in the groove just medial to the biceps tendon. Press gently inward toward the bone. You should feel a rhythmic thumping.
- Adjust if needed: If you do not feel anything, slide your fingers slightly up or down and try different amounts of pressure. Pressing too hard can actually compress the artery flat and block the pulse you are looking for.
Some people find the pulse more easily a few centimeters above the elbow crease, along the inner edge of the biceps, rather than right at the crease itself. In individuals with more subcutaneous fat or very muscular arms, you may need to press a bit more firmly. If the arm is cold or the person is dehydrated, the pulse can be faint regardless of technique.
Why Blood Pressure Cuffs Rely on This Spot
The brachial artery is the standard site for measuring blood pressure because it sits at roughly heart level when you are seated with your arm on a table, and it is large enough that the sounds of blood flow resuming after cuff inflation are clearly audible. This method dates back to 1905, when a Russian surgeon named Nikolai Korotkoff demonstrated that inflating a cuff above systolic pressure blocks flow through the brachial artery, and then slowly deflating it produces characteristic tapping sounds as blood pushes past the narrowed artery.2PubMed Central. History and evolution of blood pressure measurement Those sounds, now called Korotkoff sounds, mark the systolic and diastolic readings that appear on your chart.
When a clinician takes your blood pressure manually, they place the stethoscope bell or diaphragm directly over the brachial artery pulse, just below the cuff’s lower edge. Research comparing stethoscope placement has found that Korotkoff sounds are heard more clearly when the bell of the stethoscope is placed directly over the maximal brachial artery pulse rather than simply over the general area of the inner elbow.3PubMed. Quality of Korotkoff sounds: bell vs diaphragm, cubital fossa vs brachial artery This is one reason why knowing exactly where the artery is, rather than guessing, produces more accurate readings.
Automated home blood pressure monitors work differently. Instead of listening for Korotkoff sounds, they detect oscillations in cuff pressure caused by the artery pulsing beneath the cuff. A sensor picks up those tiny pressure waves and a built-in algorithm estimates systolic and diastolic values from the oscillation pattern.4Nature. Automated ‘oscillometric’ blood pressure measuring devices: how they work and what they measure Because the cuff wraps around the whole upper arm, you do not need to place a stethoscope in exactly the right spot. But the cuff still needs to sit over the brachial artery for the oscillations to register properly, which is why most cuff instructions tell you to align a marker arrow with the inner arm.
Checking the Brachial Pulse in Infants
In adult first aid, you typically check for a pulse at the neck (carotid artery). In infants, the neck is short and chubby, making the carotid difficult to find, so guidelines direct rescuers to check the brachial pulse on the inner upper arm instead. The technique is similar to the adult version: you press your fingertips on the inside of the baby’s upper arm, between the elbow and shoulder, feeling for a pulse against the humerus bone.
This sounds straightforward, but studies have found it is surprisingly unreliable in practice. In one study testing over a hundred CPR-certified individuals, fewer than half correctly palpated the brachial pulse in an infant, compared to over 80 percent who could detect the heartbeat simply by placing an ear against the infant’s chest.5PubMed. Determining the pulse for infant CPR: time for a change? The difficulty comes from the tiny size of the artery and the amount of soft tissue covering it. If you are in a situation where you need to check an infant’s pulse and cannot feel the brachial artery, listening for a heartbeat on the chest (or watching for signs of circulation like movement or breathing) is a practical backup.
Anatomical Variations That Move the Artery
Anatomy textbooks present one standard route for the brachial artery, but real bodies vary. A systematic review and meta-analysis found that the standard anatomy holds in roughly 90 percent of people, with variations present in about 10 percent.6PubMed. Anatomical Variations of the Brachial Artery: A Systematic Review and Meta-Analysis Other literature puts the variation rate as high as 20 percent, depending on how broadly “variation” is defined.7PubMed Central. High Bifurcation of the Brachial Artery: An Embryological Overview
The most common variation is a “high bifurcation,” meaning the artery splits into its two branches (radial and ulnar) somewhere in the mid or upper arm rather than at the elbow. When this happens, you might feel a pulse in the expected spot but it comes from only one of the two branches rather than the full brachial artery, or the pulse may be in a slightly different position. In one documented case, the brachial artery split just a few centimeters below the armpit, with the resulting radial and ulnar arteries taking unusual positions.8PubMed Central. Anomalies of radial and ulnar arteries In another case, the artery bifurcated at the middle third of the humerus and was entirely absent from the cubital fossa, meaning a clinician looking for it at the elbow crease would not have found it at all.9PubMed Central. Bilateral Median Nerve and Brachial Artery Variations in the Arm: A Case Report
These variations tend to show up more often on the right arm and more often as a one-sided phenomenon. The meta-analysis reported that among individuals with brachial artery variations, about 65 percent had them on the right side, and roughly 71 percent had the variant on only one arm.6PubMed. Anatomical Variations of the Brachial Artery: A Systematic Review and Meta-Analysis For most people, these differences are invisible and have no effect on daily life. They become relevant during medical procedures, vascular surgery, or when a blood pressure reading seems unexpectedly inconsistent between arms.
When Medical Procedures Involve the Brachial Artery
Clinicians sometimes need to access the brachial artery directly. Arterial blood gas sampling, where a small amount of blood is drawn from an artery rather than a vein to measure oxygen and carbon dioxide levels, occasionally uses the brachial artery when the radial artery at the wrist is not accessible. Cardiac catheterization procedures have also historically used the brachial artery as an entry point, though the radial and femoral arteries are now more common choices.
The safety profile for brachial artery puncture is generally good. A study of over 1,500 arterial punctures at the brachial site found an overall complication rate of about 2 percent, mostly consisting of temporary pain or tingling in the arm. Hematoma (a localized collection of blood under the skin) occurred in only about 0.06 percent of cases, and none of the complications resulted in loss of limb function or lasting injury.10PubMed. The safety of brachial artery puncture for arterial blood sampling That said, the brachial artery runs very close to the median nerve, and nerve injury from needle puncture or from pressure applied afterward is a recognized risk. Literature on arterial access procedures reports nerve injury rates for brachial and axillary access as high as 9 percent in some settings, compared to rates well below 1 percent for femoral (groin) access.11PubMed Central. Avoiding peripheral nerve injury in arterial interventions
A rarer complication is a pseudoaneurysm, where the artery wall does not seal properly after a puncture and blood leaks into the surrounding tissue, forming a pulsating pocket. Brachial artery pseudoaneurysms occur in fewer than 1 percent of catheterization procedures, but they can grow large and cause serious problems including hemorrhage, nerve compression, and loss of limb function if not treated.12PubMed Central. Giant 20 × 35 cm brachial artery pseudoaneurysm after fistulogram treated with surgical resection of pseudoaneurysm and patch angioplasty of brachial artery These complications are relevant context if you have ever wondered why a nurse holds firm pressure on the puncture site for several minutes after an arterial blood draw. That pressure is closing the hole and preventing a hematoma or pseudoaneurysm from forming.
Common Mistakes That Make the Pulse Hard to Find
If you have tried feeling for the brachial pulse and come up empty, the most likely culprits are technique-related rather than anatomical. A few of the most frequent errors:
- Using your thumb: The thumb has its own arterial pulse (from the princeps pollicis artery), which can trick you into feeling your own heartbeat instead of the other person’s.
- Pressing too hard: Heavy pressure collapses the artery and silences the pulse. Start light and increase gradually until you feel a throb.
- Searching too far laterally: Many people aim for the center of the inner elbow, but the artery sits medial to the biceps tendon, closer to the body’s midline than you might expect.
- Tense arm muscles: A flexed bicep pushes tissue over the artery. The arm needs to be extended and relaxed, preferably supported on a surface.
Cold environments and low blood pressure also make the pulse harder to detect. If you are checking your own pulse for exercise tracking, the radial artery at the wrist is usually easier and just as useful. The brachial artery matters most for blood pressure measurement and for clinical assessments where the wrist pulse is weak or absent.
The Brachial Artery in Vascular Health Testing
Beyond blood pressure, the brachial artery has become an important tool in cardiovascular research. A test called flow-mediated dilation (FMD) uses ultrasound to measure how much the brachial artery widens after a brief period of restricted blood flow. A cuff on the upper arm or forearm is inflated for several minutes to temporarily block flow, and when it is released, healthy arteries dilate as blood rushes back through. The degree of dilation reflects how well the endothelium, the inner lining of the blood vessel, is functioning.
Research into FMD technique has found that the results depend heavily on where the cuff is placed. When the cuff is placed on the upper arm (above the point where the artery is being imaged), the peak dilation is substantially larger and takes longer to occur compared to forearm cuff placement. One study found that upper-arm cuff placement produced an average peak dilation of about 16 percent after roughly 109 seconds, while forearm cuff placement produced only about 7 percent dilation after 67 seconds.13PubMed Central. Flow mediated dilation of the brachial artery: an investigation of methods requiring further standardization These differences matter because researchers need consistent methods if FMD is going to be useful as a screening tool for early cardiovascular disease.
FMD testing is mostly a research and specialty clinic tool at this point, not something you would encounter in a routine physical. But it illustrates why the brachial artery gets so much attention in medicine: it is large enough to image clearly, accessible without any invasive procedure, and responsive enough to reflect the health of your vascular system as a whole. Ultrasound of the brachial artery also serves as an educational tool for teaching basic vascular imaging principles, including how to measure blood flow velocity and calculate the volume of blood moving through the vessel.
When One Arm Reads Differently Than the Other
If you have ever had your blood pressure checked on both arms and gotten different numbers, the brachial artery is the reason those numbers matter. A consistent difference of more than 10 to 15 mmHg in systolic pressure between the two arms can signal narrowing or blockage in the arteries feeding one side, a condition linked to higher cardiovascular risk. The anatomical variations discussed earlier can also contribute to discrepancies. If the brachial artery on one side has an unusual branching pattern, the cuff may not compress the vessel in quite the same way, potentially affecting the reading.
This is one reason clinicians sometimes check blood pressure in both arms during an initial visit. If there is a meaningful difference, the arm with the higher reading is typically used for future measurements, because it more accurately reflects central arterial pressure. For home monitoring, pick whichever arm your doctor advises and stick with it for consistency. If you notice a new or widening gap between the two arms, mention it at your next appointment. The issue may not be the cuff or your technique; it could be the artery itself telling you something worth investigating.