- Great battery life
- Comfortable to wear
- Easy to sync
- No ANT+
- Coros app doesn't really do anything
The Coros Heart Rate Monitor is designed to help runners, cyclists, and functional fitness types get comfortable and accurate heart rate data.
While smartwatches offer heart rate monitoring from the wrist, accuracy can suffer during HIIT workouts or any activity where you get excessive flexing in the arm.
The Coros Heart Rate Monitor is designed to live on the upper arm, which doesn’t suffer from the same movement as the wrist, and while it still uses an optical sensor, it should produce more reliable data.
It’s different from chest straps, which use an EKG sensor. While this is generally more accurate than an optical sensor, it has downsides. We’ve had duff data from ECK chest straps before, and you often need to wet the sensor to get a good connection. And wearing a chest strap isn’t particularly comfortable, especially for women.
We’ve lived and sweated with the Coros Heart Rate Monitor. Here’s how it performed.
Price and competition
The Coros Heart Rate Monitor is only available in the US right now, but we’re expecting widespread availability come September 2023. That's slightly limiting, but we're sure it will be all forgotten come the holiday season.
It comes in at a competitive $79.99 – which compares favorably with the rest of the market.
The Polar Verity Sense works in much the same way and can be positioned on the upper or lower arm – but that comes in at $99.99.
The Wahoo Kickr Fit, which also works from the arm, costs $79.99 – so that’s a viable alternative. But the Coros does offer far better battery life.
So in terms of value for money, it’s a win for the Coros. However, both those rivals pack in ANT+, so if that's something you need the Coros HRM is out of the equation.
Design and comfort
The Coros Heart Rate Monitor itself is a small lightweight unit that sits in a stretchy neoprene strap.
It’s incredibly lightweight and once positioned on your arm, is barely noticeable. We had a grey band to try, which looks decent. It has EXPLORE PERFECTION etched onto the band, which seems a little excessive – but it’s at least quite subtle.
The strap was a little fiddly to get to the right size. It requires a bit of trial and error on the buckle, and then once it’s on your bicep, there’s a Velcro clasp to finish the job.
The stretchy band does a good job of staying in place without feeling like it’s constricting your arm, and the heart rate module can be slid around to get a good connection with the skin. It’s lightweight, comfortable, and once sized, easy to pop on and off.
Once it’s placed on the skin, the Coros quickly fires into life and is available to pair.
While you should pair it with the Coros app to get started, and receive any critical firmware updates, there are no tracking capabilities in the app. So that’s the first, and probably last time you need to deal with it via the Coros app itself.
In terms of features, there’s not much extra on offer here than heart rate tracking. Garmin uses its HRM-Run/Tri/Pro devices as Running Dynamics sensors that offer a bunch more data from tracked runs.
There are also a few extra things to note. There's no underwater HR here, so it's no good for swimmers.
Optical sensors also have issues with tattoos – and also dark skin tones. So if that affects you, an EKG chest is still the best bet.
Connectivity and features
The Coros Heart Rate Monitor uses Bluetooth 5.3 to connect to a range of devices, from sports watches, smartwatches, static bikes like Peloton, and, of course, smartphone apps.
We tested it with the Garmin Forerunner 255, as well as iPhone via the Strava and MapMyRun apps. It was seamless to sync every time.
The key thing to know here is that it doesn’t support ANT+. That’s not a huge deal these days, as most new equipment and sports watches support Bluetooth. If you do have an older Garmin, cycling computer, or gym equipment, you’ll need to check the Coros is supported.
Coros says that ditching ANT+ enables huge battery life savings.
There's also no memory on board here – so you can't go off and record a session and upload it to your preferred service afterward. It needs to be used in tandem with your preferred app or service, and have the wearables device or smartwatch along for the ride.
Heart rate accuracy
The key thing here is accuracy, and it stood up well in our testing.
We took it on a bunch of runs, and yoga classes and did some static workouts in the garden, and found a good level of accuracy, that was pretty much glued to a traditional chest strap.
I’ve never enjoyed running with a chest strap, and even less so doing floor-based workouts. Having the chest strap buckle digging in, or feeling the unit when lowering down, is just a major turn-off.
So the great thing about the placement on the arm is that it rarely feels in the way.
Taking one of our testing runs, we took an hour run over mixed terrain with some hill sprints, and matched the Coros HRM up against a Garmin HRM-Pro chest strap.
We saw an average of 164 bpm vs. 165 bpm. The Coros saw a max HR of 183bpm and 185bpm on the chest strap. So it was a solid performance, and across all of our runs we saw negligible differences in data.
We’d say that the optical sensor of the Coros still lagged the chest strap in getting up to the highest peaks. That max heart rate captured was achieved on a hill sprint, and it’s telling that the max HR was a couple of bpm behind – which was evident in real-time.
But with such little difference between the two, it's impossible to say with any certainty which was correct and we have no reservations about the accuracy on display here.
The spec sheet for the Coros shows an excellent battery life, and that was certainly borne out in our testing.
Coros claims 38 hours of tracking and 80 hours on standby. That means there’s a much better chance of it being ready to go when you are.
After two weeks with three workouts, the battery still stood at 83% when we picked it up for another session. So not only does it offer long battery life when working out, but it’s also effective at managing power consumption when shoved in a drawer.
Most chest straps will also last months between charges – but when the battery does go, you need to big out a coin cell. What’s more, you generally find this out when the device fails to pair.
Conversely, the Coros Heart Rate Monitor charges in around an hour, using a proprietary magnetic charger from USB. So when it does need recharging, it’s almost hassle-free.
Should you buy it?
The Coros Heart Rate Monitor will always be a niche product. We’d heartily recommend it for gym-goers and those who enjoy functional fitness and HIIT, whether you pair it to a wearable or just to a smartwatch.
We don’t see too much benefit for runners and cyclists, as we’ve seen good heart rate accuracy on most smartwatches and sports devices these days.
Given that the Coros Heart Rate Monitor uses optical sensors that collect data from the arm, accuracy is still slightly shy of a chest strap, which places an EKG straight on the heart. But the differences are minuscule, and we much prefer the ease of use of the Coros, both in terms of battery life and comfort.
How we test