A handful of smartwatches can measure blood pressure, but only a few do it with meaningful accuracy, and none are currently cleared by the FDA in the United States. The Samsung Galaxy Watch series, the Huawei Watch D2, and the Omron HeartGuide are the most widely recognized options, each using a different approach to measurement. Which one is worth your money depends on where you live, how accurate you need the readings to be, and whether you’re willing to calibrate the device regularly with a traditional cuff.
Samsung Galaxy Watch Series
Samsung’s Galaxy Watch is the most popular smartwatch with a blood pressure feature. Starting with the Galaxy Watch Active2 and continuing through the Watch3 and all later models, Samsung built blood pressure monitoring into its Samsung Health Monitor app. The watch uses optical sensors on the back of the case to track how blood pulses through vessels in your wrist. It then estimates your systolic and diastolic pressure based on changes in those pulse patterns.
There’s a significant catch: Samsung requires you to calibrate the watch against a traditional upper-arm blood pressure cuff before you can use the feature, and you need to recalibrate every 28 days. Research on smartwatch blood pressure accuracy shows that if recalibration happens on schedule, readings drift by only about 0.6 mmHg between calibrations. But if your blood pressure happens to be unusually high or low during calibration (from stress, caffeine, or even white-coat anxiety), every reading until the next calibration will be skewed.
The bigger limitation is availability. Samsung’s blood pressure feature is region-locked and not available in the United States. It’s approved in South Korea, parts of Europe, and a handful of other markets. If you’re in the U.S., the feature simply won’t appear in the app.
Huawei Watch D2
The Huawei Watch D2 takes a fundamentally different approach. Instead of relying solely on optical sensors, it has a miniature inflatable airbag built directly into the watch strap. This 26.5 mm airbag inflates against your wrist, mimicking the squeeze of a traditional blood pressure cuff. A high-precision pressure sensor, mini pump, and the airbag work together to take oscillometric readings, the same basic method your doctor’s office cuff uses.
This design gives the Huawei Watch D2 a real accuracy advantage over purely optical smartwatches. It’s certified as a medical device under Europe’s CE MDR regulations and is one of the roughly 10% of blood pressure devices on the market approved by STRIDE BP, an international organization that validates blood pressure monitors. The European Society of Hypertension’s guidelines recommend ambulatory blood pressure monitoring at 15 to 30 minute intervals, and the Watch D2 is designed with that kind of frequent measurement in mind.
The downside: Huawei products have limited availability in the U.S. and no FDA clearance for blood pressure measurement. If you’re in Europe or Asia, it’s currently the most clinically validated smartwatch option.
Omron HeartGuide
The Omron HeartGuide is a wrist-worn device from a company known for traditional blood pressure cuffs. Like the Huawei Watch D2, it uses an oscillometric method with an inflatable band. However, independent testing has raised concerns about its accuracy. A study comparing the HeartGuide to a validated clinical monitor found that it significantly underestimated both systolic and diastolic blood pressure. Systolic readings were off by an average of 10.4 mmHg, and diastolic by 3.2 mmHg. The researchers concluded the HeartGuide is not a suitable replacement for existing blood pressure monitors. Heart rate measurements, by contrast, were accurate in most conditions.
Cuffless Optical Monitors
Most smartwatches that claim blood pressure capability, including Samsung’s, use a cuffless optical approach. The sensor shines light into your skin, detects blood flow patterns, and calculates something called pulse transit time: how fast each pulse wave travels from your heart to your wrist. Because stiffer arteries (associated with higher blood pressure) transmit pulses faster, the watch can estimate your pressure from that speed.
The problem is that many things besides blood pressure affect how fast pulses travel. Cold temperatures, stress, and even the natural variability of artery elasticity in the wrist can shift readings. The brachial artery in your arm has higher variability in stiffness independent of blood pressure compared to larger arteries closer to the heart, which makes wrist-based optical sensors inherently less reliable than an upper-arm cuff.
The Aktiia bracelet is one cuffless optical device that has undergone clinical validation. In testing against a standard cuff, its systolic readings fell within 5 mmHg of the reference about 53% of the time, within 10 mmHg about 86% of the time, and within 15 mmHg about 96% of the time. Diastolic accuracy was somewhat better: 69% within 5 mmHg and 95% within 10 mmHg. That’s useful for spotting trends over time, but it means any single reading could be off by a clinically meaningful amount.
The FDA’s Position
The U.S. Food and Drug Administration issued a safety communication warning consumers not to use unauthorized blood pressure devices, specifically calling out software features on smartwatches and smart rings that claim to measure blood pressure. As of now, no smartwatch has received FDA 510(k) clearance for blood pressure monitoring in the U.S. The FDA maintains a searchable database where you can check whether a specific device has been authorized (look for product code DXN).
This doesn’t mean every smartwatch blood pressure feature is useless. It means none have passed the FDA’s bar for accuracy and reliability as a medical device in the American market. If you’re using one of these watches to track general trends, that’s a different proposition than relying on it to diagnose or manage hypertension.
Getting Accurate Readings From a Wrist Device
Even the best wrist-based blood pressure device will give unreliable readings if you don’t position your arm correctly. The core issue is gravity: if your wrist is above or below your heart, hydrostatic pressure shifts the reading up or down. You need your wrist at heart level for a valid measurement. In practice, this means sitting with your arm bent so your wrist rests near the center of your chest, not dangling at your side or raised above your head.
Some devices include a position sensor that guides you to hold your forearm at the correct angle. If yours doesn’t, sit at a table, rest your elbow on the surface, and bend your arm so the watch face is roughly at the height of your sternum. Stay still, don’t talk, and avoid measuring right after exercise, caffeine, or a stressful moment.
Calibration matters just as much as posture. If your watch requires calibration against a traditional cuff, do it when you’re relaxed and your blood pressure is at a typical baseline. Calibrating while stressed or rushed can anchor every subsequent reading to an inaccurate reference point, compounding the error over the entire 28-day calibration window. The further your actual blood pressure drifts from whatever it was during calibration, the less accurate the watch becomes.