The normal range for results of the A1C diagnostic test is between 4.5 and 6 percent, according to Mayo Clinic. The A1C test is used to diagnose pre-diabetes, type 1 and type 2 diabetes.
An A1C result between 5.7 and 6.4 percent indicates that a patient has pre-diabetes. When the A1C is over 8 percent, this means that a patient has likely had untreated diabetes for a long time, notes Mayo Clinic. For patients who have been diagnosed with diabetes, the target A1C is usually lower than 7 percent. Generally, the higher the A1C is, the more estimated average blood sugar level and the higher the risk of complications from the disease.