The glycolated hemoglobin test (HbA1c, also called hemoglobin A1c or the glycosylated hemoglobin test) is an important blood test to determine control of your diabetes. It provides an average blood glucose measurement over the past six to twelve weeks and is used in conjunction with home glucose monitoring to make treatment adjustments.

The normal range for the HbA1c test is between 4 percent and 6 percent for people without diabetes. The ideal range for people with diabetes is generally less than 7 percent.

People with diabetes who are treated with insulin should have this test four times a year (every 3 months). The test may be needed more frequently when your diabetes is not well controlled. However, the test should be performed no more often than every six weeks. Those who are not treated with insulin should have this test every four to six months.

If your A1c is this:

Your average mean daily plasma blood sugar is around this:

mg/dl

mmol/L

12.0%

345

19.5

11.0%

310

17.5

10.0%

275

15.5

9.0%

240

13.5

8.0%

205

11.5

7.0%

170

9.5

6.0%

135

7.5

5.0%

100

5.5

4.0%

65

3.5

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