TL;DRCNET Labs found AirPods Pro 3 averaged 1.67% heart rate error vs a Polar H10 chest strap, second only to Apple Watch at 0.98%.
Apple’s AirPods Pro 3 heart rate sensor averaged 1.67% error compared to a medical-grade Polar H10 chest strap in testing by CNET Labs, making the earbuds the second most accurate consumer heart rate device the publication has measured. Only the Apple Watch Series 11 performed better, averaging 0.98% error in the same test protocol.
The results, published by CNET this week, place AirPods Pro 3 ahead of every smartwatch and fitness tracker the lab has tested except Apple’s own watch. CNET’s methodology used a four-lap track protocol with the Polar H10 as the gold standard reference, a setup consistent with how exercise physiology labs validate optical heart rate sensors.
The AirPods Pro 3 use a photoplethysmography (PPG) sensor that fires infrared light at 256 times per second to detect blood volume changes in the ear canal. Apple says the sensor was trained on more than 50 million hours of data from the Apple Health Study, and the company describes it as the smallest heart rate sensor it has ever built.
The 💜 of EU techThe latest rumblings from the EU tech scene, a story from our wise ol' founder Boris, and some questionable AI art. It's free, every week, in your inbox. Sign up now!A peer-reviewed study published in PLOS Digital Health in April 2026 independently corroborates the accuracy claims. Researchers tested 40 adults across 16,735 paired heart rate measurements and found the AirPods Pro 3 averaged 2.02% deviation from a reference device. The study noted that the ear canal offers a more stable optical reading environment than the wrist because there is less ambient light interference and less motion artifact during exercise.
