The Heart Rate Monitor I Trust the Most Is Just $24 for Prime Day

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This is a love letter to my favorite heart rate monitor, the Coospo H6 chest strap, which also happens to be on sale today. This is the chest strap that I trust so much, I use it to test other devices for accuracy. And you don’t need a chest strap to be expensive to work well—this one is only $23.99 during Prime Day. 

Why this is my favorite heart rate monitor

It’s electrical, not optical. Your typical smartwatch uses a green light to reflect light off your blood vessels, which is a “good enough” way of measuring your heart rate, but is error-prone in a lot of situations. Arm-based heart rate monitors work the same way, and there are a few chest straps that use an optical sensor as well. (I’d avoid these. If you’re going to wear a chest strap, make it the more accurate electrical kind.) 

On the other hand, an electrical chest strap like the venerable Polar H10 (also on sale today, $76.19 down from $104.95) or my humble Coospo measures the electrical signals of your heart, and is far more accurate. For that reason alone, I recommend this type of monitor. You’re just going to get more reliable data. 

It’s cheap. You don’t need extra bells and whistles just to measure heart rate. Fancy monitors like Garmin’s HRM 600 have other features, like sensors to collect running dynamics and storage to collect data when you’re away from your phone. But if you just want to monitor your heart rate, that’s a simple job that even a cheapie like the Coospo can do just fine. 

The strap detaches for washing. For some reason, not all heart rate monitors have this feature. The Coospo snaps off, I wash the band in my post-workout shower, and all is right with the world. 

The battery lasts forever. The Coospo operates off a coin cell 2032 battery. I find I need to replace it about once a year. 

You don’t even need a smartwatch to use it. Since it does Bluetooth, you can pair the strap directly with your phone. (This is true of most heart rate monitors these days.) I use the free Polar Beat app when I want to bypass the phone, but the Coospo also syncs successfully with every device I’ve tried, and there have been dozens of them. Garmins, Apple Watches, even the Peloton Bike.

Coospo has made other chest straps since I bought this one. The H808S is basically the same thing, but has a little LED that lights up to show you when it’s on, which is a nice feature. It’s $26.26 today, and I’d say the extra $3 is worth it, but either is a good choice.

Looking for something else? Retailers like Walmart, Best Buy, and Home Depot have Prime Day competition sales that are especially useful if you don’t have Amazon Prime.

Walmart’s Prime Day competition sale begins at midnight on July 8 and will include deals up to 50% off. It’s an especially good option if you have Walmart+. 

Best Buy’s Prime Day competition sale, “Black Friday in July,” runs through Sunday, July 13 and has some of the best tech sales online. It’s an especially good option if you’re a My Best Buy “Plus” or “Total” member.

Home Depot extended its 4th of July sale through at least July 9, competing with some amazing deals of its own. It’s an especially good option if you’re looking for power tools, appliances, or outdoor equipment.