Medical devices can be categorized into two categories which is invasive and non-invasive method. Invasive method needs medical device to be inserted into patient body regarding to check or do the treatment on the patients. However, the non-invasive method is a way to check the health condition from the outside of the body. A common non-invasive medical device is Heart rate monitor. The function of the Heart rate monitor is determining heart rate (i.e.) beats per minute. The main aim of this work is to develop a portable device which helps to record heart rate of a person. The heart rate also referred as pulse rate, has been recognized as a vital parameter since beginning of medicine, and is directly related to person’s cardiovascular health. Heart rate or pulse recording is the most important vital parameter which helps the individual as well as doctor to spot out developing health problems. Using Heart Rate Monitor (HRM) is a more accurate way to monitor heart rate than manually taking your pulse at carotid of radial pulse. A HRM detects the electronic signal of heart and automatically computes the heart rate in BPM. Infrared light emitting diode (LED) is used to transmit the light and phototransistor works as a receiver. The Infrared (IR) sensors used uses the principle reflectance plethysmography (PPG) to sense the pulse signal from finger tip. The sensor output is read from the Arduino board, computes the BPM and display the instantaneous heart rate on LCD display module. Based on the above principle, a portable heart rate device using Arduino microcontroller is developed.