There's some misunderstanding. For a person who has not been diagnosed with diabetes, an a1c level of 6.5 is borderline, and you should take further exams to see whether you are diabetic or not. However, if you are diabetic already and want to know how is your blood sugar controlled, you'll do an a1c test. When the test result is 6.5, it means that your blood sugar for the past 3 months is well controlled. Have I made myself clear?