Heart-rate monitor Ratings Check up on your heart rate with a top heart-rate monitor. With versatile designs and features, heart-rate monitors help you keep track of every beat.

Ambient light shines through your skin and produces a video stream that looks like a dark red rectangle. Though it may be imperceptible to us, the color changes ever-so-slightly as your heart beats.

The manufacturer claims a battery life of 10 days and has the following sensors: 3-axis accelerometer, optical heart rate monitor, red and infrared sensors for blood oxygen (SpO2) monitoring and ...