Hemoglobin A1c

This lab test measures the average blood sugar level for the past 2-3 months. It is important as it can help diagnose diabetes mellitus.

Hemoglobin A1c Overview

Reviewed: April 21, 2014

Hemoglobin (A1c) is a blood test that checks the amount of sugar (given as a percent) bound to the hemoglobin in the red blood cells. This test gives an average blood sugar level over the past 2 to 3 months.

Hemoglobin (A1c) is measured as a percentage.

  • The normal level is less than 7% in a diabetic adult.
  • The normal level is less than 5% in a non diabetic adult.




Blood draw


Fasting is not required before the test.

What the results mean

Hemoglobin A1c of 5.8% to 6.4% indicates prediabetes.

Hemoglobin A1c of 6.5% and higher indicates diabetes.