The A1C test is a common blood test for people who have type 1 or type 2 diabetes. The A1C test also goes by many other names, including glycated hemoglobin, glycosylated hemoglobin, hemoglobin A1C and HbA1c.
Unlike finger sticks you can do at home, which measure your blood sugar level at a given time, the A1C test reflects your average blood sugar level for the past two to three months. The A1C test doesn’t tell you what’s happening at the moment. Instead, it helps your doctor gauge how well you’re managing your diabetes overall.
Specifically, the A1C test measures what percentage of your hemoglobin — a protein in red blood cells that carries oxygen — is coated with sugar (glycated). The higher your A1C level, the poorer your blood sugar control and the higher your risk of diabetes complications.