AirPods Can Measure Your Heart Rate, but Are They Accurate?

I wore the AirPods Pro 3 for months before I remembered they could even track my heart rate. I remember sitting in Apple's September keynote, when the company announced heart-rate tracking through your ears. Measuring the rate of your heartbeats from a pair of earbuds sounded futuristic, and the announcement drew one of the loudest rounds of applause of the keynote. Then I got home and went right back to recording every workout with my Apple Watch. There wasn't much reason to change. The Apple Watch Series 11 beat out every smartwatch I tested in our CNET Labs heart-rate comparisons against a Polar chest strap (designed explicitly to track heart rate), so I wasn't expecting a pair of earbuds to come anywhere close. The Apple Watch Series 11 still takes the crown for heart rate accuracy, but if I'd included the AirPods Pro 3 in my previous comparisons, they would've beaten out every other smartwatch on my list. The Apple Watch is our top-rated smartwatch for heart-rate tracking. Consumer health tracking started on the wrist, but it isn't staying there. Fitness trackers and smartwatches have made 24/7 heart-rate monitoring mainstream to aid in training and recovery. They've since evolved to almost clinical level of precision to help flag serious heart conditions, sleep issues and even alert emergency services with features like loss of pulse detection (on the Pixel Watch). Now we're seeing similar sensors in smartrings, earbuds, smart earrings and soon even smart glasses that can do the same from different parts of your body. Where we'll eventually wear our primary health tracker is still an open question. But to answer that, every new location has to prove it can measure those same health signals as accurately as the wrist. Wearables like the earbuds and smart rings are tracking vitals beyond the wrist. While tracking heart rate from earbuds is novel, I wasn't starting this comparison from scratch. A few months earlier, Whoop's now-infamous "thong" accessory (yes, the fitness company really makes performance underwear that lets you wear its sensor on your waist and other locations) sent me down a rabbit hole. I interviewed physicians and wearable experts about whether different parts of the body are better suited for measuring different health signals. The answer depends on what you're measuring. Fingertips, for example, work well for blood oxygen because they're packed with small blood vessels, and thinner skin lets more light pass through. Heart rate is different. In general, the closer a sensor sits to the heart (and the less that body part moves during exercise), the easier it is for a sensor-equipped device to capture a clean signal. That gives the ear a couple of advantages over the wrist. It's slightly closer to the heart and stays relatively stable while you run. But location is only part of the equation. Apple has spent more than a decade refining the Apple Watch's heart-rate algorithms. In my previous CNET Labs testing against a Polar H10 chest strap, the Apple Watch Series 11 averaged less than a 1% error rate, making it the most accurate smartwatch I've tested to date. The AirPods have different hardware and space constraints. Apple says it built its smallest-ever heart-rate sensor to fit inside the tiny buds and trained it on more than 50 million hours of Apple Health Study data. But this is still new territory. The question isn't whether earbuds can measure heart rate, it's whether they can come close to the Apple Watch. For every wearable I've tested, I use the same benchmark: the Polar H10 chest strap (CNET's gold standard in consumer HR tracking). Unlike an Apple Watch or AirPods, which estimate heart rate by shining light into your skin and measuring changes in blood flow, the Polar measures the heart's electrical signals directly. Think of it as measuring the rock hitting the water instead of the ripples it creates. Optical sensors can match that signal, but paired with enough machine learning, they can surprisingly close. The Polar H10 uses electrodes to measure the heart's electrical activity. To keep the comparisons consistent, I ran every test on the same college track using the same protocol I'd developed for previous CNET Labs smartwatch testing. Each workout covered four laps, or 1 mile. The first lap is the ramp up to raise my heart rate from resting. The next two laps are a steady cruising altitude at a medium pace through the middle heart-rate zones. And the final lap is an all-out sprint to push my body as close to my maximum heart rate as possible. Max heart rate is generally estimated as 220 beats per minute minus your age. Using the same route, pace and effort each time helps eliminate variables, so the only thing that changes is the device. Watch this: I Ran 30 Miles and THIS Is the Most Accurate Smartwatch 07:42 Before testing the AirPods, I reran the Apple Watch Series 11. I already had data from previous CNET Labs testing, but I wanted both devices to

AirPods Can Measure Your Heart Rate, but Are They Accurate?

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