A1C test result charts are available on the Mayo Clinic and Bayer Diabetes websites. These charts show the estimated average blood sugar level for each A1C level. Normal A1C levels range from 4.5 to 6 percent, states Mayo Clinic.
The A1C test is a lab test that measures glucose levels of a person for the last three months, notes the Department of Health for New York State. Results above 6.5 percent on two separate tests indicate the patient has diabetes, states Mayo Clinic. Doctors use the A1C test to confirm the presence of diabetes and track the control of blood glucose levels over time.