What is Estimated Average Glucose (eAG)?

Estimated average glucose (eAG) or "average glucose" is a way of translating A1c test results into terms that closely represent daily glucose readings. It was introduced by the American Diabetes Association (ADA) in 2010 to help people with diabetes better understand how their A1c results compare to their daily glucose readings.

Person undergoing a blood test
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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 cell, 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 determioned 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 at least twice a year and preferably four times a year (quarterly).

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 lower than your eAG. 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.

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  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). MedLine Plus. 2019.

  5. American Diabetes Association. Understanding A1C. Diabetes (online).

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