The promise of continuous, convenient blood pressure monitoring from a wrist-worn device has captivated consumers, but the reality of current smartwatch capabilities presents a nuanced picture. As of October 2026, the ability of popular smartwatches from manufacturers like Samsung and Huawei to accurately measure blood pressure without a traditional inflatable cuff remains a subject of both technological innovation and medical scrutiny. While some devices have achieved medical device certifications, others are largely considered wellness tools, prompting health organizations to advise caution.
Huawei has taken a distinct approach to blood pressure measurement in its Watch D series, which includes the Watch D, D2, and the recently released D3. These devices incorporate a miniature inflatable cuff directly into the watch band. This design allows them to perform oscillometric measurements, a method akin to that used by conventional blood pressure monitors, and is generally regarded as more accurate than purely optical estimation techniques. The Huawei Watch D2, for instance, has been recognized as the world's first wrist-worn dynamic blood pressure monitor to meet medical standards. It holds both China's Class II medical device registration and EU CE MDR certification, signifying a rigorous level of regulatory approval. Studies have affirmed that the Huawei Watch D complies with ISO 81060-2:2018 guidelines for accuracy, demonstrating mean differences between the smartwatch and reference devices that fall within acceptable limits for both resting and ambulatory blood pressure.
The latest iteration, the Huawei Watch D3, launched in September 2026, also carries China Class II medical device registration and EU CE MDR certification. This model builds upon its predecessors by employing what Huawei describes as a "light disturbance dynamic blood pressure research" approach. It combines the precision of micro-pump cuff measurements with photoplethysmography (PPG) sensors to enable continuous trend tracking. The goal of this hybrid method is to reduce the disturbance associated with frequent cuff inflation while still providing reliable data. Huawei reports the accuracy of both the Watch D2 and D3 to be within a tight margin of ±3mmHg, a standard often associated with medical-grade devices.
In contrast, Samsung's Galaxy Watch series, encompassing models from the 4 through the 8, relies primarily on photoplethysmography (PPG) sensors to estimate blood pressure. This optical method detects changes in blood volume in the wrist's capillaries. However, unlike Huawei's cuff-based system, these Samsung models necessitate regular calibration with a traditional cuff-based blood pressure monitor, typically every 28 days, to maintain a reasonable level of accuracy. Without this consistent recalibration, the accuracy of the readings is known to degrade over time.
The reliability of PPG-based smartwatches has been a point of contention in the medical community. A 2022 study published in *Frontiers in Cardiovascular Medicine* raised concerns, finding that a popular PPG-based smartwatch, specifically the Samsung Galaxy Watch Active 2, failed to meet the accuracy standards established by medical device regulators. The study reported mean errors exceeding 10 mmHg for both systolic and diastolic pressure, indicating a significant deviation from true values. Furthermore, it identified a systematic bias where the device tended to overestimate low blood pressures while underestimating high blood pressures, which could have serious implications for users with hypertension.
However, more recent research offers a somewhat more optimistic view for specific models. A prospective validation study conducted in January 2026 on the Samsung Galaxy Watch 5 found that it met ISO and IEEE accuracy criteria in most measures. This study reported negligible mean differences for both systolic and diastolic blood pressure and minimal drift in accuracy over the calibration period. Despite these positive findings, the study also noted that when the reference blood pressure was 10 mmHg away from the calibration point, the mean differences were higher, reaching 3.4 mmHg for systolic blood pressure and 5.1 mmHg for diastolic blood pressure. This suggests that while calibration helps, the device's accuracy can still be influenced by significant deviations from the calibration baseline.
The broader medical community, including authoritative bodies like the American Heart Association (AHA), remains cautious about cuffless blood pressure devices. The AHA and the 2025 ACC/AHA high blood pressure guideline explicitly recommend against relying on cuffless devices for accurate clinical measurements, diagnosis, or the management of high blood pressure. This recommendation stands until the precision and reliability of these technologies demonstrably improve across the board.
It is important to understand that many wearables estimate blood pressure indirectly, and their accuracy can be significantly influenced by a range of factors. These include the frequency and quality of calibration, the user's motion during measurement, their posture, skin tone, and the precise position of the wrist. For these reasons, smartwatches equipped with blood pressure monitoring features are generally considered most suitable for tracking trends in blood pressure rather than providing absolute values that can be used for medical diagnosis or treatment decisions. Furthermore, regulatory clearances, such as FDA clearance for a blood pressure device, do not automatically guarantee measurement accuracy, as such clearances do not always require formal accuracy testing under a standardized protocol.
While established reporting provides a clear picture of current capabilities and limitations, some claims and future possibilities remain. Some users of Samsung Galaxy Watch models have alleged high accuracy, reporting only a 1 to 3 unit difference when comparing their smartwatch readings to those from a traditional blood pressure monitor. Separately, a startup's "Signal Ring" claims to produce systolic and diastolic readings without any cuff calibration, reporting a mean error of -0.3 mmHg in a commissioned study. These claims, while intriguing, await broader independent validation.
Looking ahead, research into truly cuffless and calibration-free methods for blood pressure monitoring is actively ongoing. Scientists are exploring various advanced technologies, including radar-based sensors, tonometry, and sophisticated PPG algorithms enhanced by machine learning. However, achieving regulatory approval for these cutting-edge technologies presents a high bar. To navigate these stringent requirements, most smartwatches currently market their blood pressure features as "wellness" tools rather than medical devices, thereby avoiding the more rigorous scrutiny associated with clinical applications.
Industry forecasts suggest that smartwatches may achieve full medical device status for blood pressure monitoring within the next three to five years, as technological advancements mature and a greater body of validation studies accumulates. Still, fundamental questions persist, such as determining the optimal time interval for recalibration of cuffless devices. Google's Pixel Watch 5, expected to be released in September 2026, is anticipated to introduce a "Blood Pressure Trends" feature. This technology aims to estimate pressure from pulse-wave and motion data without requiring calibration, though it is not yet fully explained whether users will see an actual blood pressure number or merely a trend indicator. The ability of current cuffless devices to accurately track blood pressure changes during dynamic activities like exercise, sleep, and after medication adjustments also remains a subject of ongoing scrutiny and research.
In summary, while smartwatches like the Huawei Watch D series offer medically certified, cuff-based blood pressure measurements, PPG-based devices from Samsung and others require frequent calibration and are generally not recommended for clinical diagnosis by major health organizations. The future promises more sophisticated, calibration-free solutions, but for now, consumers should view most smartwatch blood pressure features as tools for tracking general trends rather than definitive medical diagnostics.