The accuracy test for the heart rate sensor on AirPods Pro 3 shows it is almost on par with that of the Apple Watch.

      In a recent evaluation by CNET Labs, Apple’s AirPods Pro 3 demonstrated an average heart rate error of 1.67% when compared with a Polar H10 chest strap, ranking them as the second most accurate consumer heart rate monitoring device after the Apple Watch, which had a 0.98% error rate. The findings, released this week, indicate that the AirPods Pro 3 outperformed all tested smartwatches and fitness trackers except for the Apple Watch Series 11. The testing protocol involved a four-lap track method, using the Polar H10 as the reference, mirroring the validation procedures adopted by exercise physiology labs for optical heart rate sensors.

      The AirPods Pro 3 utilize a photoplethysmography (PPG) sensor that emits infrared light 256 times per second to monitor blood volume fluctuations in the ear canal. According to Apple, this sensor was trained on over 50 million hours of data from the Apple Health Study and is described as the smallest heart rate sensor the company has ever produced.

      An independent peer-reviewed study published in PLOS Digital Health in April 2026 supported these accuracy claims, evaluating 40 adults with 16,735 heart rate measurements and revealing an average 2.02% deviation from a reference device. The study also noted that the environment of the ear canal affords a more stable optical reading compared to the wrist due to reduced ambient light interference and motion during exercise. However, it did point out greater variability in readings during high-intensity workouts, suggesting that while the AirPods are reliable for steady-state activities, they may be less consistent during interval training.

      It is important to note some limitations in CNET's testing, as only two complete runs of the AirPods were conducted, a smaller sample size than typically used for smartwatch reviews. CNET remains the primary source for the comparative rankings of the AirPods Pro 3 against other smartwatches, as no other lab has conducted similar side-by-side evaluations.

      Research into biometric sensing via the ear is not new, but Apple is the first to offer such a technology in a mass-market consumer audio product. The closer proximity of the ear canal's vasculature to the skin surface facilitates the ability of PPG sensors to achieve comparable or better accuracy with a smaller size compared to wrist sensors. This trend indicates a broader health tracking expansion into various body locations beyond the wrist, with each site providing unique physiological benefits.

      At a price point of $250, the AirPods Pro 3 are significantly cheaper than the $400 Apple Watch Series 11, while primarily serving as earbuds. For users seeking heart rate data during workouts without the need for a smartwatch, the AirPods present a valid alternative due to their minimal accuracy difference.

      It's worth noting that Apple does not market the AirPods as a medical device, and the heart rate feature does not have FDA clearance for clinical application, unlike the Apple Watch, which has FDA approval for its ECG and irregular rhythm notifications. The AirPods are limited to heart rate measurement and do not monitor arrhythmias, blood oxygen levels, or other clinical parameters.

      The trend of health wearables is shifting towards smaller and more diverse formats. For instance, Oura's Ring 5 tracks heart rate, temperature, and respiratory rate from the finger, and Whoop offers recovery tracking through a screenless wristband, while Google’s Fitbit Air launched at $99 with AI health coaching.

      With accurate heart rate monitoring capabilities in both a watch and earbuds, Apple has established two data collection points for the same user. This dual-device strategy is significant because heart rate data collected from different locations can enhance accuracy through cross-referencing. Though Apple has not yet disclosed plans to integrate data from AirPods and Apple Watch in real-time, the existing infrastructure allows for such aggregation through the Apple Health app.

      For competitors, the AirPods' performance sets a higher standard. Brands like Samsung, Google, and Xiaomi produce earbuds, yet none currently match Apple's heart rate monitoring precision. While the underlying PPG technology for optical heart rate sensors is well-established, Apple seems to benefit from the substantial volume of training data and the sensor's sampling rate rather than a fundamentally different technology.

      Ultimately, whether earbuds can replace smartwatches for health tracking is contingent on user needs. Heart rate is just one metric; the Apple Watch also tracks blood oxygen, skin temperature, and conducts electrocardiograms—features that AirPods do not currently provide. However, regarding heart rate measurement during exercise, the AirPods Pro 3 deliver results comparable enough to the Apple Watch to be significant.