Printed on 2/13/2026
For informational purposes only. This is not medical advice.
HbA1c (glycated hemoglobin) reflects average blood glucose over the preceding 2–3 months. This converter uses the ADAG (A1C-Derived Average Glucose) study formula to translate HbA1c percentages into estimated average glucose (eAG) in both mg/dL and mmol/L, helping patients and clinicians understand what the A1c number means in terms of daily blood sugar levels.
Formula: eAG (mg/dL) = 28.7 × HbA1c − 46.7 (ADAG formula)
Disclaimer: This tool is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about your health.
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CardiologyCalculate your 10-year risk of cardiovascular disease using the Framingham Risk Score. Based on the landmark Framingham Heart Study data.
HbA1c measures the percentage of hemoglobin proteins in your blood that have glucose attached. Because red blood cells live about 120 days, HbA1c reflects your average blood glucose over the past 2–3 months. It is the primary metric for assessing long-term glycemic control.
ADA recommends <7.0% for most adults with diabetes. <6.5% may be appropriate for selected patients without significant hypoglycemia risk. <8.0% may be acceptable for elderly patients or those with multiple comorbidities. Non-diabetic normal is <5.7%.
The ADAG formula (eAG = 28.7 × A1c − 46.7) was derived from a large study correlating continuous glucose monitoring with A1c. It provides a good population-level estimate but individual variation exists. Some conditions (hemoglobin variants, anemia, kidney disease) can affect A1c accuracy.
For diabetic patients meeting goals: every 6 months. For patients not meeting goals or after treatment changes: every 3 months. For diagnosis/screening: fasting glucose or A1c can be used. Point-of-care A1c testing provides results within minutes.