A1C
Also called: Glycohemoglobin, HbA1C, Hemoglobin A1C test
A1C is a blood test that measures your average blood sugar level over the past 3 months. It is used to diagnose type 2 diabetes and prediabetes, and to monitor how well you are managing diabetes. The result is given as a percentage: a normal level is below 5.7%, prediabetes is 5.7% to 6.4%, and diabetes is 6.5% or higher.
Diagnosis
Doctors may use the A1C test alone or with other tests to diagnose type 2 diabetes and prediabetes. A normal A1C is below 5.7%, prediabetes is 5.7% to 6.4%, and diabetes is 6.5% or higher.
When to see a doctor
If you have diabetes and your A1C result is too high, you may need to change your diabetes care plan. Ask your doctor what your A1C goal should be.
Frequently asked questions
What does the A1C test measure?
It measures your average blood glucose, or blood sugar, level over the past 3 months.
What is a normal A1C level?
A normal A1C level is below 5.7%.
What A1C level indicates prediabetes?
Prediabetes is between 5.7% and 6.4%.
What A1C level indicates type 2 diabetes?
Type 2 diabetes is diagnosed at an A1C of 6.5% or higher.
How often should people with diabetes get an A1C test?
If you have diabetes, you should have the A1C test at least twice a year.
Sources
- MedlinePlus: A1C — NIH MedlinePlus
- Intersecting Burdens: Type 2 Diabetes Diagnosis, Risk, and Pharmacological Management Among People Living With HIV. — J Pharm Pract, 2026
- Labile Hemoglobin A(LHbA): From analytical interference to clinically valuable biomarker. — Clin Chim Acta, 2026
- Pharmacological Treatment for Gestational Diabetes Mellitus: A Systematic Review and Network Meta-Analysis of 71 Randomised Controlled Trial. — Diabetes Obes Metab, 2026
- Decentralized Chronic Care Service Delivery for People Living with Type 1 Diabetes in Low- and Lower-Middle-Income Countries: A Scoping Review. — Endocr Pract, 2026
- Personal viewpoint: Risk stratification and counseling of living kidney donor candidates with prediabetes. — Am J Transplant, 2026
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.