A structured lab test from CNET has put numbers to something Apple hinted at last year: AirPods Pro 3 heart rate tracking is more accurate than most dedicated smartwatches, finishing second only to Apple Watch Series 11 in a head-to-head comparison against the Polar H10 chest strap as the reference standard.
CNET writer Vanessa Orellana ran four laps around a college track, covering 1 mile at varying intensities, with AirPods Pro 3 and five wearables recording simultaneously. The competing devices were Apple Watch Series 11, Garmin Venu 4, Google Pixel Watch 4, Samsung Galaxy Watch 8, and Amazfit Bip 6.
Apple Watch Series 11 led the field with a 0.63% error rate and an average difference of 0.89 BPM from the chest strap. AirPods Pro 3 came in second with a 1.23% error rate and a 2.02 BPM average difference, outperforming every non-Apple wearable in the test. CNET’s conclusion was direct: if you are already spending $249 on AirPods Pro 3, up from the Pro 2’s feature set, you do not need to spend another $400 on a watch solely for heart rate data.
AirPods Pro 3 use a custom photoplethysmography sensor that pulses invisible infrared light 256 times per second and measures how much of that light is absorbed by blood flow in the ear canal. Apple says it is the smallest heart rate sensor the company has ever built, and it was designed exclusively for these earbuds, a point the AirPods Pro 3 teardown illustrates well. The Powerbeats Pro 2 takes a different approach, using green LED optical sensors pulsing at over 100 times per second, and Apple has confirmed the two products do not share the same sensor technology.
To handle the motion noise that comes with running, Apple pairs the PPG sensor with accelerometer and gyroscope data, GPS input, and an on-device AI model on iPhone, hardware made possible in part by internals like the AirPods Pro 3 case’s U2 chip, producing readings that support over 50 workout types. That sensor fusion is likely why the AirPods held up well during a dynamic outdoor test rather than a controlled stationary reading.
Orellana had to complete the course three times to get a complete data set: the first attempt failed to record fully, and the second ended when a sprinkler droplet hit the stop button on her iPhone. Cold weather also presents a known limitation, because reduced blood flow in the ears can lower skin perfusion enough that the sensor cannot get a reliable reading. Fit matters too, the real-time acoustic seal test in AirPods Pro 3 helps confirm a snug ear tip fit, which is equally important for consistent sensor contact.
When AirPods Pro 3 and Apple Watch are worn together during a workout, the two devices coordinate rather than compete, providing multiple streams of heart rate data with the highest-confidence source selected automatically. For users who already own both products, that combination is a more capable setup than either device alone.
Apple had acknowledged the performance gap before launch, noting internally that Apple Watch heart rate data is “more accurate” but that AirPods “aren’t terribly far off.” The CNET numbers put a precise value on that gap, and a 1.13 BPM difference between first and second place is narrow enough that most workout users would never perceive it. The more meaningful finding is the distance between AirPods Pro 3 and the rest of the smartwatch field, which makes a reasonable case that dedicated wrist hardware is no longer a requirement for accurate exercise heart rate monitoring. Apple is also developing a next AirPods Pro with cameras and an H3 chip, suggesting the health and sensor ambitions for the line are far from finished.
