Using a top heart rate monitor is the best way to get more data from your training sessions â and that's useful whether you're a novice runner, or a serious athlete. Everyone can gain something from monitoring their heart.
And heart rate monitors are for more than sport. The latest devices can help monitor your heart rate 24/7, help spot illness, stress, tiredness â and help tell you when to take a break.
We've reviewed and tested pretty much every heart rate monitor on the market â this is our list of picks.
- Fitbit heart rate monitor guide
- Garmin's best heart rate features explained
- Apple Watch heart rate features explored
How to buy a heart rate monitor
When people ask us about buying a heart rate monitor in relation to fitness, it always comes down to the type of device they're using to work out.
Those who want to use their phone to work out will need to look for a Bluetooth-enabled strap, which will connect to apps like Runkeeper and Endomondo. However, Strava has recently cancelled support for external Bluetooth devices within its app, so bear that in mind.
Chest strap vs. heart rate monitor watch
The biggest battleground is now chest straps versus wrist devices, the latter of which use LEDs to "see" the blood pulsing through your veins.
Optical sensors are integrated into most new running watches, smartwatches and fitness trackers from the likes of Garmin, Fitbit and Suunto and Apple. But are optical heart rate monitors as accurate as chest straps?
Optical wrist wearables are far more comfortable and convenient, and, if you're running steadily, should do the job just fine. We've tested them side by side, and if you're just running steady, you shouldn't see any problems.
However, when you start moving about, doing functional fitness, or HIIT the optical sensors can't cope with the rapid rises and falls in bpm. They can also be flummoxed by movement of the wrist in exercises, and controversially, dark skin. So accuracy can even depend person to person. This is where a chest strap is better - although much less comfy to wear.
The accuracy question â what's good enough?
At Wareable, we're serious runners, but are still happy with the imperfect data from our wrist devices because of the convenience they offer. It's good and consistent enough to compare effort â and we're comfortable with the insights you get on recovery and performance that are derived from the sensors.
Not carrying two devices everywhere is much easier, and when it comes to training in HR zones, the likes of Garmin and Polar do a good job.
If you're more into functional fitness and HIIT and you demand the most accurate data possible - a chest strap is a better option.
Move away from the wrist
We should mention that there is a new breed of optical heart rate sensors that moves the tracking to the forearm and the upper arm, too. Polar, Whoop and Scosche have heart rate monitoring armbands available that claim to offer the same level of accuracy you'd get from a chest strap. There's less movement on the forearm and upper arm â although skin tone can still be an issue. There are also heart rate monitoring headphones with the ear regarded as a place to deliver reliable data.
Price when reviewed: $89.95
As we've already mentioned, if you care about accuracy then for us it's still the chest strap and the Polar H10 is the one we've found to be the most reliable.
The iOS and Android-friendly strap boasts Bluetooth and ANT+, so you can pair it to a whole host of devices and third party apps, including Garmin sports watches if you like.
It also introduces a modified design, adding silicon friction dots to help keep the strap in place, plus it's a bit more comfortable to wear.
It still uses an ECG-style sensor that detects the electrical activity of the heart to deliver your BPM readings, but a new measuring algorithm and extra interference-preventing electrodes help improve accuracy.
It's waterproof, so you can go swimming with it although it won't track heart rate intervals in the water. There's onboard memory to store a training session, just in case your phone or wearable dies on you.
We've been using it to test against a lot of the new fitness trackers and smartwatches that have landed at Wareable HQ recently, mainly throwing data into the Polar Beat app, which is built for heart rate based training. It's still the chest strap we go back to and can comprehensively say it still delivers the goods.
Sample Polar H10 data:
Whoop Strap 3.0
Price when reviewed: $25 a month subscription
The Whoop Strap 3.0 offers something totally different â if you're willing to subscribe to the $30 a month subscription. While it takes the form of a wristband, it can be placed on the forearm and upper arm to help you get more reliable readings when training.
There's no display, but it will auto-detect exercise, which can be tagged in the app later, so there's no fiddling pre-workout. You will then get full heart rate data from your session, synced into the Whoop app.
But Whoop aims to do more than just track sessions. It also tracks the effect of workouts, using its Strain score. This is done by monitoring heart rate variability after your session - measuring the gaps between heartbeats to see how affected you were. It will try and augment this with activity from the rest of your day, and your sleep, to recommend when you need to rest and when you need to push.
For those whose training is a bit more serious, this is pretty unique data. While Garmin produces comparable information, that is limited to running workouts. So if lifting, CrossFit or other types of sport are your bag, the Whoop Strap 3.0 comes recommended.
Check out our Whoop Strap 3.0 review
Sample Whoop Strap 3.0 data:
Price when reviewed: $79.99
If you want more from your chest strap, the MyZone MZ-3 goes beyond churning out simple bpm (beats per minute) recordings. You earn points based on your bpm. It's also being integrated into a whole host of fitness classes at studios and gyms globally.
Rather than simply scoring highly based on a high reading, the MyZone studies your effort over time and creates a golf-style handicap for your level. Your aim is to better your own performance, and like golf, MyZone adds a gamification element enabling you to compete against others, even at vastly different abilities.
Design-wise, it's your pretty conventional chest strap with a red elasticated strap, which comes in three sizes, along with the module you can clip out. It also has an internal memory - capable of storing 16 hours of data - so you don't always have to exercise while carrying your smartphone, which is useful for gym classes.
It offers a 7-month battery life from a single charge and is waterproof down to 10 metres so you can take it for a swim too.
If you do keep your smartphone nearby, you'll also benefit from the live stats along with the league tables, personal goals and challenges to keep you motivated.
In MyZone-supporting gyms this data often appears on big screen during your classes. The app has improved over the years too, adding new features that puts that heart rate monitor to better use.
Sample MyZone data:
Price when reviewed: $59.95
The H9 is the newest addition to Polar's heart rate chest strap collection and it essentially replaces the older H7, coming in cheaper than the H10 too.
What's the big difference between the H9 and the H10? There are a few things. It misses out on the new Pro strap, which is designed to offer a more comfortable fit. It sticks with the strap used on the now retired H7. In our time with it, comfort was a major issue. If anything, we preferred the slightly more hugging fit.
It also doesn't offer the ability to store workouts or pair to two Bluetooth connections at the same time. If you can live without those features, you're still getting a heart rate monitor that delivers where it matters.
It's the same ECG-style method of tracking your heart to give you the best accuracy. It has ANT+ and Bluetooth connectivity support and works with a host of third party apps. We've also successfully paired it up with Garmin, Polar and Suunto watches too. You're also getting a 30 metre water resistant rating, making it suitable for tracking heart rate for swimming.
Polar's companion Beat app is great if you're very much focused on heart rate-based training, letting you zone in on the metrics and insights that matter. We've used it for plenty of running (both indoor and outdoor) and like the H10, it's accurate and the most reliable way to get data you can trust.
Sample Polar H9 data
Price when reviewed: $72.99
The Garmin HRM-Run as the name suggests, is angled at runners. So along with measuring your heart rate with an ECG-style sensor, it's also going to serve up a raft of additional metrics to delve into post and during a run.
Those advanced running stats are cadence, vertical oscillation, ground contact time, ground contact time balance, stride length and vertical ratio. If you know what those terms mean (if not, check out our running watch data guide), these can help to identify areas of your technique and running form that could help improve running style and hopefully get you running better and quicker.
Back to heart rate monitoring, and the HRM-Run connects to devices using ANT+ and has a 5ATM waterproof rating making it safe for the pool. It's powered by the kind of coin cell battery you'll find powering a lot of watches. That should last you up to a year, before you need to pop it out and replace it.
We've use the HRM-Run for plenty of testing including putting it to the marathon test where it was comfortable to wear and crucially delivered the data that mattered. If you've got an ANT+ friendly device and want that extra hit of accurate HR data and advanced running metrics, it's definitely one to check out.
Sample Garmin HRM-Run data
Scosche Rhythm24 HR
Price when reviewed: $99.99
So you don't like wearing a chest strap and you don't trust your wrist-based monitor to do the business. There is another option â and based on our experience, it's one that does deliver the goods on the accuracy front.
Scosche launched the first heart rate monitoring armband before Wahoo and Polar decided to offer something similar. Like its predecessor, the Rhythm24 HR sits on the forearm to track your BPMs. The idea is that there are less motion artefacts that can impact on a reading that can happen further down on the wrist.
It's available in a range of different coloured bands, is waterproof and has the ability to store workouts onto the wearable and then sync it later. The LED lights built-in indicate your current heart rate zone while training and can also indicate when you need to stick it back on the charger.
The Rhythm24 is ANT+ and Bluetooth Smart-compatible so you can use it with a whole bunch of third-party fitness apps, sports watches and sports equipment. There's also the Scosche companion app where you'll find dedicated profiles for a range of activities. It's clean, simple and very easy to use keeping you firmly focused on that heart rate data.
We've tried the Rhythm24 HR and the sweat-proof and water resistant wearable passed the high intensity interval test. Plus, it was also very comfortable to wear during our workouts. It's also capable of measuring heart rate in the water as a bonus.
Bottom line, Scosche proves you can comfortably wear a heart rate monitor elsewhere on your body and still get those results you crave.
Check out our Scosche Rhythm24 HR review to find out more about the heart rate monitoring armband.
Sample Scosche data:
Price when reviewed: $199.99
Garmin's entry level running watch doesn't scrimp on heart rate smarts â it has a built-in optical heart rate monitor using the company's Elevate technology â the same you'll find on the brand new Garmin Fenix 6. While it doesn't produce the same amount of analysis from HR data as Garmin's top devices, it will still give you a VO2 Max reading after an outdoor run, and this is tracked in the Garmin Connect app.
It still suffers the same dropouts and inaccuracies as the rest of the Garmin range at high load - so it's best for steady runners. Of course, you can connect a Garmin heart rate strap if you need.
But at this price, it's a solid performer in the Garmin range.
Sample Forerunner 45 heart rate data:
Polar Vantage V
Price when reviewed: $475.99
Polar's heritage is built on heart rate monitors, so it's no surprise to find that it's making the biggest progress as far as improving readings from the wrist. With the new Vantage V and cheaper Vantage M and Ignite multisport watches, it's come up with some of the best in the business.
Polar still uses an optical based sensor, but its sought to improve accuracy and reliability by adding additional LED sensors to penetrate the skin deeper to take a reading. It's also using more LEDs and including electrode sensors to ensure the sensor is in proper contact with the skin.
That heart rate monitor is used for a whole host of features on the new Vantage watches. So along with real-time heart rate data during exercise, you also get VO2 running estimates, calorie burn based on maximum heart rate and more advanced metrics like cardio load and muscle load for those really serious about training.
In addition to those hardcore training metric, it'll also continuously measure heart rate 24/7 pinpointing when heart rate is at its highest and lowest to help accurately calculate calorie burn.
We've throughly put it to the test and found the monitor to be a solid performer for activities like running and interval training where most optical sensors are susceptible to having problems. It's a similar story for the Vantage M, which offers the same sensor tech inside of a more affordable watch design.
Polar still regards its H10 chest strap as the best heart rate solution for serious athletes and is still required to carry out a number of the training-centric tests available on the Vantage V (like the orthostatic test). But on the whole, we were very impressed with how well Polar does dishing out heart rate metrics.
Check out our full Polar Vantage V review and Polar Vantage M review to see how the two shaped up in other departments. Also, check out the Polar Ignite, which will also feature the same heart rate tech for a bit less money.
HR sample data: Polar (left) and Garmin chest strap (centre)
Garmin Forerunner 945
Price when reviewed: $599.99
The Forerunner 945 sits at the top table of Garmin's sport watch line up, and is designed with hardcore triathletes in mind. It makes use of Garmin's latest Elevate optical HR tech - so it's reliable for runs although problematic for HIIT. You can still pair with a chest strap for better data.
You can train in heart rate zones, receive heart rate alerts, and broadcast heart rate data over ANT+ with paired devices. You can go swimming with it of course, but you'll need to pair it with Garmin's HRM-Tri or HRM-Swim bands to get reliable data in the water.
And it will produce a tonne of useful metrics from you heart rate data. Training Effect, Training Load, recovery and VO2 Max are all gleaned from tracked runs, using Firstbeat's heart rate variability algorithms. It's actionable and interesting data that can help you learn more about your session.
Outside of workouts, you can also perform HRV stress tests to asses how well recovered your body is for taking on your next workout session. Additional heart tate-based metrics including lactate threshold can be unlocked when it's paired with Garmin's Running Dynamics Pod.
In our testing putting it up against Polar's H10 chest strap, it actually fared really well and is definitely an improvement on what we've seen from Garmin's heart rate setup in the past.
Check out our full Garmin Forerunner 945 review.
Sample Forerunner 945 data:
HR sample data: Garmin (left) and chest strap (centre and right)
Garmin HRM Tri
Price when reviewed: $129.99
There are a lot of wrist-based sports watches that claim to offer accurate heart rate monitoring in the water. We are talking about the likes of the Polar Vantage V and Vantage M. The Scosche Rhythm24 armband and the Polar OH1+ (which can be worn on your goggles) promises accuracy on par with a chest strap too. We haven't tested those comprehensively enough to say they do deliver the goods, so for now we are going to stick with a chest strap that does.
The HRM Tri strap from Garmin is a real pro tool for triathletes. It's an ultra-small and light (a mere 49g) heart rate strap that adds considerable bike and running smarts to some of the pool functions of the HRM Swim.
With a built-in accelerometer that'll deliver cadence, vertical oscillation and ground contact time data (like Garmin's HRM Run) while on two legs, plus HR stat storage while actually underwater, this is one of the most rounded tools for the three disciplines out there. Garmin has also ensured there are no exposed seams and all edges are soft and rounded, to prevent rubbing or any wetsuit-doffing difficulties.
Apple Watch Series 5
Price when reviewed: $399
We can debate whether you should call the Apple Watch Series 5 a sports watch or a smartwatch, but there's no doubting it's become a solid device for heart rate monitoring â and many of its features are now bordering medical grade.
From a fitness point of view, we've put it through the same rigorous testing as we do with all of the wearables on this list and it really impresses where a lot of wrist-based monitors falter. We're talking high intensity interval training.
Data is viewable inside of Apple's own Workout app but the benefit of having a strong collection of third party Watch apps means you can also view that data in places like Strava and Runkeeper.
If you don't care about working in heart rate zones though, it's well equipped for taking reliable resting heart rate readings throughout the day and with the addition of an ECG, it's now fit to tap into heart rate readings to detect serious heart issues including atrial fibrillation.
That data can be viewed inside of Apple's own Health app and also be exported to a PDF to be shared with medical professionals.
Along with the improved hardware, Apple has clearly done some software tinkering too to improve the performance of its heart rate monitor in a big way.
While Fitbit and Samsung do offer decent heart rate monitoring solutions on their smartwatches, it's Apple's that we think does the best job of making it all work.
Sample Apple Watch Series 5 data:
Fitbit Charge 4
Price when reviewed: $149.95
The Fitbit Charge 4 is the company's latest flagship tracker and it's packing in the same HR setup as the Charge 3. So expect a similar performance. Like any wrist-based HR monitor, it can struggle at high intensity, but it will still be good enough for workouts in the gym and on the road if you're not too worried about pinpoint accuracy.
It's once again relying on Fibit's own PurePulse technology to deliver features like real-time heart rate bpm readings while working out and the ability to train in heart rate zones. Fitbit has added some useful heart rate-related features like Active Zone Minutes, which now rewards you for hitting certain heart rate zones. You will also get buzzed when you hit a new heart rate zone during exercise.
Much like the Apple Watch, it's not just about using heart rate for exercise here. The Charge 3 also monitors heart rate continuously to assess your current state of fitness through resting heart rate readings.
It also uses that sensor to unlock mindfulness features like stress tracking through guided breathing exercises. The heart rate sensor is also put to use during sleep monitoring to produce additional metrics to help analyse the quality of your time in the land of nod.
In our testing, it's a similar story to what we got with the Charge 3. For some steady runs, it held well against a chest strap but faltered when you throw in high intensity intervals into those runs. Post workout, the Charge 4 was better at analysing data in the app than it was during a workout. When it comes to continuous heart rate monitoring, it's certainly a different story and that real-time data feels a lot more reliable.
If you're put off by the technical graphs of its competitors, Fitbit's app is one of the most accessible ways to track your workouts and HR data too. it's not a perfect tracker by any means, but definitely more reliable than a lot of fitness trackers we've tried. Also, If you're looking for something with a slimmer design that offers heart rate tracking and is cheaper, definitely take a look at the Fitbit Inspire HR.
Have a read of our in-depthFitbit Charge 4 review for more insights into Fitbit's flagship fitness tracker.
Fitbit Charge 4 sample data:
HR sample data: Chest strap (top) and Fitbit (bottom)
Garmin Vivosmart 4
Price when reviewed: $89.99
The Vivosmart 4 is one of the best fitness trackers out there thanks to its slimline design but also because it because it does to enhance the use of its onboard heart rate monitor to offer more insightful data.
It can of course be used to measure exercise intensity although you'll be relying on the motion sensors to track that activity as there's no GPS support. There's support to take VO2 Max measurements, so the maximum amount of oxygen your body can utilize during exercise. Just note that you'll need to do a few workouts to get this calibrated.
Like Fitbit's tracker it can also offering continuous heart rate monitoring during the day to deliver those resting heart rate readings that can indicate your current levels of health and fitness.
In addition to that, it'll also take heart rate variability measurements to activate stress tracking and put Garmin's new Body Battery feature to good use. This feature aims to give you a better insight into how well recovered your body is for your next workout session. It does that by taking into account your stress level (measured using heart rate variability), recent physical activity and how much sleep youâve been getting giving you a score as a percentage.
Performance-wise, the Vivosmart 4 isn't a tracker designed for people with serious athletic ambitions and that's reflected in the performance of the heart rate sensor. It's good for casual users who want to monitor their fitness levels, but it might let you down when things get more intense.
For a surprisingly slender tracker though, the Vivosmart 4 does a whole lot with the heart rate monitor it manages to squeeze in. If you do want something more feature-packed (but minus the Body Battery feature), you can always go for the Vivosport instead.
Check out orour full Garmin Vivosmart 4 review.
Garmin Vivosmart 4 sample data
HR sample data: Garmin (left) and Polar chest strap (right)
Withings Steel HR Sport
Price when reviewed: $199.95
The Withings Steel HR Sport is a stylish hybrid that will give you a similar performance to what the Nokia Steel HR delivered in terms of heart rate monitor performance and that's a good thing.
If you're thinking, wait, Withings? Yes, the co-founder of Withings has bought back the business he sold to Nokia. The Steel HR Sport is the successor to the Steel HR and if you want a reliable heart rate monitor hidden beneath a stylish analogue-style watch, this should be your one.
With the screen baked into the top of the watch face you can now view real-time heart rate data during your workout. Additional heart rate based features include the ability to take VO2 measurements to assess your fitness level. Unfortunately you cannot adjust heart rate zones, for anyone planning to rely on it for a HIIT class.
In testing, the experience was very good and it even held up in some interval training where most optical sensors falter badly to keep up with the rapid change in heart rate. Live readouts tended to trail behind the Polar H10 chest strap we tested it against. Once the session was over though, that data seemed to correct itself in the graphs. The final result was exceptionally close; the Steel HR Sport can keep up.
In the companion Health Mate app you'll be able to view your current heart rate data if you're working out with your phone nearby. It keeps things simple when your session is done and you need to pore over the data.
You'll certainly get more advanced heart rate based metrics elsewhere, but in terms of a hybrid that can handle being put to the sweaty test in the gym our out on a run, the Steel HR Sport does a fine job.
You can check out our full verdict on the sleek hybrid in our Withings Steel HR Sport review to find out how its other features fared in our testing.
Sample Withings Steel HR data:
HR sample data: Withings (left) and Polar chest strap (right)