Hemoglobin A1c (HbA1c) with mass concentration measurement from whole blood

The hemoglobin A1c (HbA1c) test gives you and your doctor a clear picture of your average blood sugar levels over the past two to three months, which makes it one of the most important tools for detecting prediabetes, diagnosing diabetes, and checking how well your current treatment plan is working.

Unlike daily blood sugar checks, HbA1c gives a broader picture of how well your body manages glucose over time, which is especially useful for diagnosing or monitoring diabetes.

This test uses a small sample of blood, usually drawn from a vein in your arm at a lab, clinic, or your doctor's office. In some settings, a quick fingerstick sample may be used instead, and the entire visit typically takes only a few minutes from start to finish.

A small blood sample is taken from your arm, typically using a fingerstick. The test measures the percentage of hemoglobin molecules coated with glucose.

No fasting or special preparation is needed before an HbA1c test, so you can eat and drink normally beforehand. After the blood draw, you may notice slight soreness or a small bruise where the needle was inserted, but you can return to your usual activities right away.

No special preparation is needed, but inform your provider about recent illnesses or medications that might affect results. The process takes a few minutes, and results are usually available within days.

Doctors commonly order this test to screen for type 2 diabetes, evaluate symptoms such as increased thirst, frequent urination, or fatigue, monitor blood sugar control in people already diagnosed with diabetes, and assess risk in those with a family history of diabetes or obesity.

Doctors order HbA1c to diagnose type 1 or type 2 diabetes, assess diabetes control in people already diagnosed, or screen for prediabetes.