Glucose level should fall into a range of 80 to 160 milligrams per deciliter, according to WebMD. Factors that impact the reference range include the type of blood glucose test and the patient's age and eating schedule prior to testing.
In a fasting blood glucose test, the patient cannot eat or drink for eight hours prior to testing, states WebMD. Normal values are less than or equal to 100 milligrams per deciliter. For a two-hour postprandial test, the patient is to eat a meal exactly two hours prior to testing. For patients under 50, the value should be less than 140 milligrams per deciliter. For patients between 50 and 60, the value should be less than 150 milligrams per deciliter. For patients over 60, the value should be less than 160 milligrams per deciliter. A random blood sugar test requires no specific preparations, and results in the normal range are between 80 and 140 milligrams per deciliter.