What is the A1C test?

The A1C blood test, also called the hemoglobin A1C test or glycohemoglobin, provides information about your average blood glucose levels for the past 2 to 3 months. People with diabetes should have the A1C test at least twice a year. Your doctor uses the results of your A1C tests to see whether you need changes in your diabetes medicine, meal plan, or physical activity routine to keep your diabetes under control.