The Galaxy Watch 4, one of the many items revealed at the Samsung Unpacked event, has a number of features that help readers monitor their health and potential warning signs before they become serious. So does it have a built-in ECG sensor that will let users monitor their own heart rates? The answer is yes.

The Galaxy Watch 4 and Galaxy Watch 4 Classic, both, do have ECG sensors, according to its spec sheets. This means both the watches will be able to monitor a person’s heart rate in real-time and provide live ECG readings to them. According to Samsung, the ECG sensors are not intended to be a replacement for traditional diagnosis and treatment, and encourages users to use the Watch 4's information only under proper supervision and with advice from a primary care provider. It'll also only be available in certain regions, and the function is also limited to the watch when it is paired to Samsung Galaxy devices only -- meaning you won't be able to use it when you pair the watch with a non-Galaxy Android device. There's a workaround for older watches, though.

ECG is short for electrocardiogram, which records the electrical signal coming from the human heart in order to monitor for differences in the pattern. Samsung says the ECG sensors are not intended to be used by patients with known arrhythmias except for atrial fibrillation, which can be detected via ECG. On-demand ECG readings are becoming a more common feature of modern smartwatches to help both users and healthcare providers have a more complete picture of a user's health.

The ECG readings within the Galaxy Watch 4 are controlled by something called the Samsung Bioactive Sensor, an instrument that obtains readings from three separate sensors while running on a single chipset. The sensors include ECG, PPG (Photoplethysmography), and BIA (bioelectrical impedance analysis). PPG is another way of monitoring heart rate via a photosensor on the surface of the skin that observes circulation, and BIA detects body composition, though Samsung warns the latter is not accurate in all cases.

The Samsung Galaxy Watch 4 is currently one of the best smartwatches on the market for Android users. It's also packed with a ton of fitness features, which makes it a reliable activity tracker too.

The Galaxy Watch 4 is the latest version of Samsung's smartwatch line, which contains multiple features designed to help users monitor their health.

The Samsung Galaxy Watch 4 comes with the latest OneUI Watch platform and is a great option for Android users.
Brand
Samsung
Display
1.2-inch Corning Gorilla Glass DX Super AMOLED 396x396 (42mm) or 1.4-inch Corning Gorilla Glass DX Super AMOLED 450x450 (46mm)
CPU
Exynos W920
RAM
1.5GB
Storage
16GB
Battery
247mAh (42mm) or 361mAh (46mm)

The Galaxy Watch 4 Classic looks like a classic timepiece, but also contains various sensors designed to help users monitor their health.

The Galaxy Watch 3 also had an ECG sensor, and in late 2020 the FDA approved the use of the Samsung Health Monitor app to give on-demand ECG readings to those wishing to monitor their own heart rate. Such sensors have also found their way into other smartwatches, including the Apple Watch and the Fitbit Sense.