What is Estimated Average Glucose (eAG)?

Estimated average glucose (eAG) is an estimate of your average blood sugar (glucose) levels over two to three months. It indicates how well you are controlling your diabetes. Also known as an average glucose level, eAG translates your A1C blood test results from a percent into milligrams per deciliter (mg/dL), the measurement used in home blood glucose monitors.

Understanding your eAG can help improve your diabetes management. Introduced by the American Diabetes Association (ADA) in 2010, eAG helps explain how A1C results relate to daily glucose readings. For example, a 6.0% A1C represents an average daily blood sugar reading of 126 mg/dL.

This article discusses estimated average glucose, how it is calculated, and what it means for your diabetes care.

Person undergoing a blood test
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How eAG Is Calculated

Both A1C testing and daily glucose readings provide useful information in the management of diabetes, but they are expressed in different ways. Daily glucose meter readings are a direct measurement of the amount of glucose in blood at the time a sample is taken and is expressed as milligrams of glucose per deciliter of blood—for example, 154 mg/dL.

A1C also uses a blood sample, but it looks at the percentage of hemoglobin, a protein in red blood cells, that has glucose attached to it (glycated hemoglobin). This reveals what an individual's average blood glucose level has been for the past two to three months. An A1C of 7% means that 7% of the total hemoglobin in a blood sample is glycated.

The eAG is determined using a straightforward mathematical formula that converts percentage of glycated hemoglobin as determined by an A1C test into the unit you're used to seeing on your glucometer: mg/dL: 28.7 X A1C – 46.7 = eAG.

Knowing your eAG can help with diabetes management by:

  • Confirming self-monitoring tests or practitioner-ordered blood tests
  • Providing an overall look at how a treatment plan is working
  • Illuminating how healthy lifestyle choices can impact blood sugar control

While A1C and eAG levels will differ depending on several factors, including age, sex, activity level, etc., the ADA recommends a target eAG of 154 mg/dL (A1C = 7%) for most adults with diabetes who are not pregnant.

A1C and eAG Equivalents At-a-Glance
A1C (percentage) eAG (mg/dL)
6.0% 126 mg/dL
6.5% 140 mg/dL
7.0% 154 mg/dL
7.5% 169 mg/dL
8.0% 183 mg/dL
8.5% 197 mg/dL
9.0% 212 mg/dL
9.5% 226 mg/dL
10.0% 240 mg/dL

A1C/eAG vs. Daily Monitoring

While A1C/eAG values are important for long-term diabetes management, they can’t replace daily blood glucose tests. Neither is indicative of current blood sugar levels. You need that information one or more times a day in order to adjust your insulin dose, food intake, and activity level.

The American Diabetes Association recommends that you get an A1C test twice a year if you are meeting glycemic goals and at least every three months (and as needed) if your therapy recently changed and/or you are not meeting treatment goals.

Average Glucose Reading on Meters and eAG

Most blood glucose meters used for daily testing can provide an average of all readings over the past several weeks or months. This average is not the same as the eAG. Even if you test your blood 10 times a day or more, you are only getting a reading of what your glucose is at that moment.

In fact, the average determined by your glucose meter is likely to be either lower or higher than your eAG. (If you measure sugar only postprandially, eAG will be lower than meter sugar, and if you measure sugar only preprandially, eAG may be higher than meter sugar. As a result, either direction is possible.) This is because the eAG represents an average of your glucose levels 24 hours a day and over a much longer period of time. Therefore, eAG is more accurate.

By combining your eAG number with your glucose meter’s average number, you are getting a valuable and comprehensive picture of your overall diabetes management. This will help you in making healthy goals and choices to achieve appropriate glucose control.

A Word From Verywell

Testing your blood sugar levels via any method can trigger strong feelings. Be gentle with yourself and remind yourself that you are not a number. Make sure you have a supportive care team to help you reach your treatment plan goals, adjusting as needed without judgment.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Dib JG. Estimated average glucose: a new term in diabetes controlAnn Saudi Med. 2010;30(1):85. doi:10.4103/0256-4947.59375

  2. Sherwani SI, Khan HA, Ekhzaimy A, et al. Significance of HbA1c test in diagnosis and prognosis of diabetic patientsBiomark Insights. 2016;11:95–104. doi:10.4137/BMI.S38440

  3. American Diabetes Association. Diabetes Pro. eAG/A1C Conversion Calculator.

  4. Wisse B. Estimated average glucose (eAG). MedlinePlus.

  5. American Diabetes Association Professional Practice Committee. 6. Glycemic targets: Standards of medical care in diabetes—2022Diabetes Care. 2022;45(Supplement_1):S83-S96. doi:10.2337/dc22-S006

Additional Reading

By Gary Gilles
Gary Gilles is a licensed clinical professional counselor (LCPC) who has written about type 1 diabetes and served as a diabetes counselor. He began writing about diabetes after his son's diagnosis as an infant.