How to Use Heart Rate Monitoring on Your Smartwatch

How to measure heart rate on your smartwatch

Modern smartwatches have a wide array of heart-rate monitoring features. That includes passive all-day monitoring as well as spot checks for specific metrics. Some will even alert you if your heart rate suddenly spikes when it shouldnt. The most advanced devices also have FDA-cleared electrocardiograms that may help detect atrial fibrillation.

These are impressive features considering that, just a decade ago, smartwatches were basically pedometers. In practice, heart rate monitoring can be a helpful tool for people hoping to understand more about their bodies or measure their fitness progress over time. For instance, some athletes prefer to train in heart rate zones which is hard to do unless you can check it in real time. There have also been several stories of people who say their smartwatches saved their lives thanks to abnormal heart rate alerts.

That said, its important to remember that these arent medical devices. At the end of the day, theyre not capable of diagnosing you with any sort of condition. And, even if they were, doctors are still on the fence about how to handle wearable data that consumers collect on their own.

There are nuances to how these features work and plenty of reasons why you might get inaccurate readings.First, well cover how heart rate monitoring works and how to measure your heart rate. Then well get into what EKG-capable smartwatches can and cannot do and how to use the EKG feature with the current crop of smartwatches.

How optical heart rate sensors work

The vast majority of wearables use a photoplethysmography (PPG) sensor the green LEDs you see when you flip the device over. The LEDs shine light into your skin; the light thats refracted back is translated by an algorithm into heart rate data. That includes your resting heart rate but also other metrics like VO2 Max and heart rate variability.

While optical heart rate sensors have gotten better over the years, wrist-based PPG sensors still arent always accurate. A recent study found that these sensors didnt work as well on darker skin or people with obesity. The wrist is also not the best place for a PPG sensor. Theres a lot of noise from your arm movements, and a companys algorithm has to be able to effectively filter that out. Thats why you could wear the same smartwatch on each arm and still get slightly different readings.

Fit is also an important factor. It varies from smartwatch to smartwatch, but here are a few general tips for getting the most accurate data possible.

• Wear the watch about one finger length above your wrist bone
• Make sure theres good contact between the sensor array and your skin
• Tighten the strap during exercise. You may also want to wear the device higher on the wrist.
• Wipe the sensor array clean whenever it gets dirty

Viewing heart rate and settings

Once youve paired your smartwatch, you should dive into the settings in your watchs companion app. Thats where youll get to customize how often your watch measures your heart rate. Some watchesmeasure heart rate continuously by default; others will measure periodically to help extend battery life.

For example, the Apple Watch measures your heart rate periodically when youre still and while walking. It only measures continuously when youre in a workout and for the three minutes after during recovery. You dont have the option to change that. However, other devices like Garmin and Samsung watches may let you have more of a say. Each smartwatch maker designs their app differently, but you can usually find heart rate settings in your devices settings or a health settings menu.

Your watch may also be capable of low and high heart rate alerts. This means youll get a notification if, while at rest, your heart rate goes below or above a certain threshold. So if youre sitting still and your heart rate spikes to 120 beats per minute, you might get a notification. Many watches will let you customize the range for these alerts.

Below, weve outlined how to access these settings for some of the most popular devices and how to measure your heart rate.

Apple Watch

To access heart rate settings, open the Watch app and scroll down the list of installed apps to Heart. From here, you can enable a variety of health measurements:

• Toggling on Cardio Fitness Notifications will tell you when it deems your cardio fitness is low.
• Enabling Irregular Rhythm notifications means youll get notified if the watch identifies heart rhythms that may indicate atrial fibrillation.
• You can also set ranges for High Heart Rate and Low Heart Rate notifications. These notifications alert you when youve passed an abnormal threshold while youre inactive.

Again, none of these are diagnostic features.

• Click the digital crown to bring up your apps
• Tap the Heart app (The app features a red background with a heart on it.)
• From there, you can manually start a heart rate reading
• You can also scroll down to view your resting heart rate and walking average heart rate

Fitbit trackers and smartwatches

To access heart rate settings:

• Tap your profile icon in the upper left corner
• Scroll down to Settings
• Tap Activity & Wellness
• Tap Heart Settings
• From here, you can set customized high and low heart rate alerts, as well as heart rate zones for exercise

• Tap your profile icon in the upper left corner
• Select the devices profile
• Tap High & Low heart rate to customize these alerts.

• From the clock face, swipe up to see current heart rate
• You can also view your rate in the Exercise app during exercise
• Certain clock faces will also feature heart rate as a complication
• You can also view in further detail from the Fitbit app dashboard

Samsung Galaxy Watches

To access heart rate settings on the Galaxy Watch 4 and Watch 4 Classic:

• Head to the Samsung Health app on your watch
• Swipe down to Settings
• Tap Measurement and select the Heart Rate section
• From here, you can select whether you want to measure continuously, periodically (once every 10 minutes while still), or manually only

On Samsungs Tizen watches:

• Press the power button on the watch
• Head to the Samsung Health app
• Swipe to Heart Rate and scroll to the bottom of the screen
• Tap HR and stress measurement
• After that, the options should be the same as above

To set up high / low heart rate alerts:

• Head to the Samsung Health app
• Tap Heart rate
• Scroll down to HR and Stress Management or Auto HR settings
• Set your watch to measure heart rate continuously
• Tap More Options or the three dots
• Tap HR alert settings
• From here, you can customize your alerts

To manually measure heart rate:

• In the Samsung Health app, tap Heart rate
• Tap Measure

About EKGs

There are only a handful of smartwatches that have been cleared by the FDA to measure EKGs in the US. So even if the smartwatch you buy supports this feature, youll have to check whether its been granted regulatory clearance in your country.

Assuming it has, EKGs on smartwatches work by reading electrical signals from your heart. The smartwatchs heart rate monitor acts as an electrode, and by touching your finger to the case / digital crown, you create a closed circuit. After a short period of time, youll be told whether your heart rhythm for that particular reading and only that reading shows a normal rhythm or signs of atrial fibrillation.

It bears repeating: no watch can give you an actual medical diagnosis. The most that you can do with this information is export it to a PDF that you can then share with your doctor. If youve got a clean bill of health from your doctor, you may not need to use this feature at all, and thats perfectly fine!

You should also be aware that you may get a few inconclusive readings. There are several reasons why that can happen. First, you generally have to remain very still to take these EKG readings if youre fidgety, that could result in an inconclusive result. Likewise, your skin might be a little wet, and that can screw up a reading.

Each smartwatch maker will have its own suggestions for how to troubleshoot, but the gist is to relax and keep still while using the EKG feature.

Apple Watch

You can only take EKGs on the Apple Watch Series 4, 5, 6, and 7.

• Open the Health app on your phone and follow the prompts, or tap Browse > Heart > Electrocardiograms > Set Up ECG app
• You should then see the EKG app on your watch
• Tap the EKG app on your wrist
• Touch the Digital crown with a finger from your opposite hand
• Wait 30 seconds for the watch to take a reading

• Open the Health app
• Tap Browse > Heart > Electrocardiograms
• From there, you should see a list of your readings
• Tap the one you want to generate a report for
• Tap Export a PDF for your doctor
• You can also tap the Share button to print or email the PDF, as well as upload it to services like Dropbox

Samsung Galaxy Watch

Only the Samsung Galaxy Watch Active 2, Galaxy Watch 3, and Galaxy Watch 4 support EKG readings.

• First, make sure your watch and phone are on the latest software
• Open the Samsung Health Monitor app on your watch
• Tap Download App. This should bring up the app download page on your phone.
• Tap Install
• Launch the Samsung Health Monitor app
• Tap continue and fill out information prompts
• Tap Finish. You should see a button that says Get Started.
• Youll then have to follow some more onscreen prompts
• Select which wrist youll wear the watch on
• Hit Done
• You should now be able to take an EKG on your watch

• Open the Samsung Health Monitor app on your phone
• Tap ECG and select View History
• Select the report you want to export
• Tap Share This Report
• Select the format youd like to send (PDF, email, etc.)

Fitbit Sense and Charge 5

Only the Fitbit Sense and Charge 5 can take ECG readings at this time.

The ECG app should already be on your watch or tracker, but if not, heres how to install (or uninstall) the app:

• Tap your profile icon in the upper left corner
• Select device profile
• Tap Gallery
• You should see the High/Low heart rate app and the EKG app
• Tap the app icon to install / uninstall

• Head to the Discover tab in the Fitbit app
• Scroll down to Assessments & Reports
• Select Heart Rhythm Assessment
• Read through the educational materials
• Open the ECG app on your watch or tracker.
• Place your finger and thumb on the edges of the case
• Wait 30 seconds and then view your results

• Tap the Discover tab in the Fitbit app
• Scroll down to Assessments & Reports
• Select Heart Rhythm Assessment
• Tap View Results
• Select which one you want to generate a report for
• Tap Export a PDF for your doctor

Withings ScanWatch

While Withings has multiple EKG-capable watches, only the ScanWatch is cleared for use in the US.

• Open the Health Mate app
• Select Devices, then ScanWatch
• Tap More Settings, and then ECG
• Select which wrist youre wearing the watch on
• On your watch, use the side button to scroll to ECG Mode
• Press the side button
• Place your fingers on the top ring for 30 seconds

• Your results should automatically appear in your Health Mate app feed
• Tap your results
• Scroll down to Share a Health Report and follow the prompts to create a PDF

The best way to monitor your heart rate with a smartwatch

Wearables are getting serious about health, and the ability to track your heart rate is becoming the norm.

Long gone are the days when wearables smartwatches and fitness trackers were little more than souped-up pedometers.

Health and wellness features, such as heart-rate monitoring and pulse-oximeter tracking, have become increasingly popular in wearable devices.

But why measure your heart rate? Can you rely on your wearable to track it accurately? Which wearables offer more sophisticated heart-health features? And how can you use your wearable to get the best out of it? Read on to find out.

Or, head straight to all thebest smartwatchesfrom our tests to see which come out on top.

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Why monitor your heart rate?

If you have any concerns about your heart, you should, of course, see your doctor. Assuming your interest is more casual, a heart-rate-monitoring wearable can be a big help in helping you get the most from your workouts.

By monitoring your heart rate, you can make sure you're pushing yourself hard enough during bouts of high-intensity exercise and recovering enough afterwards.

Longer term, keeping an eye on your heart-rate patterns can help you notice what may be causing spikes during everyday life and tell you a lot about your cardiovascular health.

Wearables that collect data on your heart rate can also give you more accurate feedback on other aspects of your health - for example, your sleep, calorie burn, stress levels and VO2 max (an estimate of the maximum amount of oxygen that you use during exercise - and therefore, a measure of your aerobic fitness).

Best fitness tracker with heart rate monitor

If you don't want a smartwatch, and you'd rather just have something lightweight that you can slip on your wrist and forget about, there are plenty of fitness trackers offering heart-rate monitoring.

Fitbit Charge 5 (130)

This lightweight fitness tracker might catch your eye if youre looking for a device you can wear all day and night. It has a built-in GPS tracker so you can leave your phone at home when youre out and about too.

It has a good set of heart-rate monitoring features including 24/7 heart rate monitoring, Active Zone Minutes (a feature that uses your heart rate to guide you towards your desired exercise intensity level), heart-rate variability and Cardio Fitness Level (a measurement of how well your body uses oxygen when youre working your hardest).

Fitbit also has a compatible ECG (Electrocardiogram) app, which assesses your heart for rhythm irregularity and allows you to share the results with your doctor. As always, you shouldn't take results as gospel, and should always contact a health professional if you have any concerns.

Like the sound of all the heart-rate monitoring features this tracker has to offer? Read ourfull Fitbit Charge 5 reviewto find out how accurate and easy to use it really is.

Best smartwatch with heart-rate monitor

If youre looking for something a little more advanced, its worth considering a smartwatch. These usually offer all of the same features as fitness trackers as well as having the ability to link together notifications from your smartphone - and often on a much bigger screen.

Huawei Watch GT 3 (200)

This smartwatch has fairly advanced features given its price, including letting you answer and reject phone calls. It also has a 46mm AMOLED touchscreen, so you can see everything at a glance.

Huawei claims that the Watch GT 3s TruSeen 5.0+ heart sensor presents a newly upgraded heart-rate module that improves the accuracy of the health data it produces. This watch will show you your heart rate 24/7, as well as daily heart-rate ranges (including during exercise) and resting heart rate. Youll be alerted of any especially low or high heart rates too, and theres a pulse oximetry function to measure the amount of oxygen in your blood.

You can also track over 100 different sports and sync this watch with a range of selected gym equipment.

Find out exactly how well this smartwatch performed in our accuracy and ease of use tests by reading ourfull Huawei Watch GT 3 review.

We see big differences in how accurately wearables can measure your heart rate, though. Some manage this very poorly, while others only manage to report accurately in certain conditions (such as struggling during low-intensity exercise, but getting more accurate at higher intensities). These include wearables at the cheaper end of the market, as well as more expensive models.

Apple Watch and other smartwatches with advanced heart-rate features

Released in 2018, the Apple Watch Series 4 was the first smartwatch to offer ECG (electrocardiogram) readings directly from your wrist via an electrical heart-rate sensor.

The sensor measures the electrical signals in your heart to check for atrial fibrillation, or AFib (irregular heart-rate rhythms), which can put you more at risk of stroke. You can download readings into a PDF to share with your doctor.

It also has an optical heart-rate sensor (light from the sensor penetrates the skin to estimate heart rate). This measures your heart rate throughout the day and calculates various metrics for you, including the average heart rate while you're walking, your Heart Rate Variability (HRV) and heart rate during a workout, and Breathe (guided breathing) sessions.

You can also check your heart rate at any given moment by opening the Heart Rate app, and you can turn on the option to get notifications if your heart rate goes above or below a chosen beats per minute (BPM).

The more recent Apple Watch Series 8 and Series 9 also offer all of these features - some earlier models have some, but not all (not the ECG feature, for example).

However, the Apple Watch is expensive compared with other smartwatches. Read our review of the Apple Watch Series 9 (from 429) to see how well it performs.

Alternatively, compare all Apple Watch models in our Best Apple Watch to buy guide.

Other smartwatches for tracking heart health

If you want to keep costs down (or you dont have an iPhone to link an Apple Watch to), there are other watches available with heart-health features.

The Fitbit Sense (220) has a number of heart-rate features to rival Apple. It has standard heart-rate monitoring, can take ECGs and even combines your heart rate with your skin temperature sensor readings to report on your stress levels.

Sounds appealing? Discover if it impressed in our lab tests in ourfull Fitbit Sense review.

If youre an Android user, the Samsung Galaxy Watch 6 might catch your eye. Alongside the usual heart-rate monitoring, it also has the ability to monitor your blood pressure or perform an ECG test on your heart rhythms. It can estimate your VO2 max (a measure of your aerobic fitness) too.

Read our fullSamsung Galaxy Watch 6 reviewto see how it fared in our rigorous performance tests.

Looking to stick to a stricter budget? The Oppo Band (35) offers both heart rate and blood oxygen monitoring, plus 11 activity-tracking modes and sleep tracking. It lacks some key features such as GPS tracking though, but packs in plenty considering its low price.

Read our fullOppo Band reviewto see exactly how accurate and easy to use this fitness tracker is.

Specialist heart health wristwatches: Omron HeartGuide

Some wearables go beyond this, making heart health their USP.

The Omron HeartGuide (499) is one such device and was marketed as the world's first clinically validated wearable blood pressure monitor.

It promises to monitor your blood pressure, steps, distance, calories and sleep, and it displays some (limited) notifications from your smartphone. Omron says the HeartGuide can also measure your heart rate, but it will do so only when you ask it to measure your blood pressure.

You'll need nimble fingers to take it on and off, though, which you'll need to do each time you want to do the washing up or go for a swim. It can survive being splashed with water while you wash your hands, if you're careful, but it can't survive being submerged in water. The watch also feels heavy and cumbersome.

Note that Omron says you shouldn't use the Heart Guide if you've had a mastectomy. Traditional blood pressure monitors can carry similar warnings.

Head to our guide on thebest blood pressure monitorsfor more handy hints and tips to get the most for your money.

How to make sure you're tracking your heart rate accurately

There are a few things you can do to give your wearable the best chance of tracking your heart rate accurately.

• Make sure your smartwatch or tracker is sitting snugly but comfortably on your arm, with the sensors flat against your skin above the wrist bone
• Keep the smartwatch or tracker clean (following the manufacturer instructions, to avoid damaging it). Sweat can also interfere with readings
• If you have poor circulation or you just feel cold, warm up a little before taking a reading
• Smoking or drinking alcohol before taking a measurement can cause your heart rate to differ from your normal readings. Try taking a measurement again later.

Tattoos and heart-rate sensors

A number of manufacturers say that having tattooed wrists can interfere with heart-rate monitoring. For example, Apple states that the ink, pattern, and saturation of some tattoos can block light from the sensor, making it difficult to get reliable readings. Garmin has a similar statement on its website.

If you have one heavily tattooed wrist, wear your wearable on the other one if it's clear for everyday use. Most smartwatches and fitness trackers have settings so you can select what wrist youre wearing it on, so it shouldnt matter if its your dominant or non-dominant hand.

See all our smartwatch reviews and fitness tracker reviews.