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A1C to eAG Calculator

Convert your Hemoglobin A1C percentage to Estimated Average Glucose (eAG) to better understand your blood sugar management.

Medically Reviewed by Dr. Rizwan Khalil (Chairman & Medical Specialist) — Last updated August 2026

A1C Converter

Convert HbA1c to eAG

%

Enter A1C to calculate...

Reference Ranges (A1C)

Normal
< 5.7%

Healthy blood sugar control.

Prediabetes
5.7% - 6.4%

Heightened risk for developing diabetes.

Diabetes
≥ 6.5%

Requires diagnosis and management.

Understanding A1C and Estimated Average Glucose (eAG)

The Hemoglobin A1c (HbA1c) test measures the percentage of your red blood cells that have sugar-coated hemoglobin. Because red blood cells live for about three months, the A1C test reflects your average blood glucose levels over the past 2 to 3 months. To make this percentage easier to understand on a day-to-day basis, healthcare professionals translate A1C into an estimated average glucose (eAG) number.

The Formula

The widely accepted formula developed by the ADAG (A1C-Derived Average Glucose) study group is:

eAG (mg/dL) = 28.7 × A1C − 46.7

To convert the result to mmol/L, divide the mg/dL value by 18.0182.

Interpreting Your A1C Results

The American Diabetes Association (ADA) provides the following guidelines for A1C percentages:

  • Normal: Below 5.7%. This indicates healthy blood sugar control and a low risk for diabetes.
  • Prediabetes: 5.7% to 6.4%. Individuals in this range are at a heightened risk for developing type 2 diabetes. Lifestyle modifications, such as improved diet and exercise, are highly recommended to prevent disease progression.
  • Diabetes: 6.5% or higher on two separate tests indicates a diagnosis of diabetes.

Frequently Asked Questions

What is the difference between A1C and eAG?

A1C is given as a percentage representing sugar-coated hemoglobin over 3 months. eAG translates that percentage into the same mg/dL or mmol/L units you see on your daily glucose meter.

How often should I get an A1C test?

If you have diabetes, it is usually recommended 2 to 4 times a year depending on how well your blood sugar is controlled. If you do not have diabetes but are at risk, once a year or as advised by your doctor.

Can anemia affect my A1C results?

Yes, conditions that affect red blood cells, like iron-deficiency anemia or hemoglobin variants, can falsely elevate or lower A1C readings. In these cases, a fructosamine test may be used instead.

Is 6.0% A1C bad?

An A1C of 6.0% is in the prediabetes range. It indicates elevated risk for developing type 2 diabetes and suggests that lifestyle interventions should be considered.

How can I lower my A1C?

Lowering A1C involves consistent carbohydrate management, regular physical activity, weight loss if applicable, and taking prescribed diabetes medications as directed by a healthcare provider.

Medical Disclaimer: This calculator is for informational and educational purposes only. It is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider. Read full disclaimer →

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