In general, the normal range for a diabetic person's blood sugar is between 70 to 130 milligrams per deciliter before eating and no higher than 180 milligrams per deciliter one to two hours after eating, according to the American Diabetes Association. However, individual blood sugar targets may vary among people.
The normal blood sugar range for diabetics over the age of 20 when fasting should be lower than 100 milligrams per deciliter, according to WebMD. If a patient takes insulin, her blood sugar should measure around 100 milligrams per deciliter before starting exercise. A normal blood sugar range for people at bedtime should measure between 100 and 140 milligrams per deciliter.