A pulse sensor is a highly recommended product that counts heart-rate in a precise manner. It’s a plug-and-play sensor for Arduino meaning that it works instantly without requiring additional work which makes it a very simple, breath taking, reliable, and fun product. Students, athletes, makers, artists, game and mobile developers, and many others benefit from it through incorporating it into their projects. It basically combines amplification, noise cancellation circuitry with a simple optical heart rate sensor in order to get the pulse readings. The power required is only 4mA current draw at 5V which makes it perfect for mobile applications.
All you have to do is to clip the pulse sensor to your finger tip, or your earlobe, you then plug it into the 3V or 5V Arduino and that’s it! It’s ready to read heart rate. Note that no soldering is required since the 24" cable on the Pulse Sensor is terminated with standard male headers.
An example of an Arduino code and a processing sketch for visualizing heart rate data is available for you to check it out.