A Blood Glucose Monitor, also referred to as a glucometer, is a medical device for determining the approximate concentration of glucose in the blood. It can also be a strip of glucose paper dipped into a substance and measured on the glucose chart. It is a key element of home blood glucose monitoring (HBGM) for people with diabetes mellitus or hypoglycemia. A small drop of blood, obtained by pricking the skin with a lancet, is placed on a disposable test strip that the meter reads and uses to calculate the blood glucose level. The meter then displays the level in units of mg/dL or mmol/L.If you have diabetes, you will likely need a blood glucose meter to measure and display the amount of sugar (glucose) in your blood. Exercise, food, medications, stress, and other factors affect your blood glucose level. Using a blood glucose meter can help you better manage your diabetes by tracking any fluctuations in your blood glucose level.