Average Glucose to HbA1c Converter

Your meter app reports a 90 day average of 156 mg/dL. Your doctor and the lab both talk in A1c percent instead. It is the same information sitting on two different scales, and without a way to move between them you cannot really tell whether the last quarter went well, or whether the medication change your doctor made in March did anything at all.

The bridge is the ADAG formula from 2008: average glucose equals 28.7 times A1c minus 46.7. This box runs it backwards, A1c equals the average plus 46.7 divided by 28.7, so 154 mg/dL returns 6.99 percent. The output carries an ADA band label too: under 5.7 normal, 5.7 to 6.4 prediabetes, 6.5 and above diabetes. The equation describes a population average, and individuals glycate hemoglobin at different rates.

Only feed it a genuine average built from many readings across roughly three months, the kind a CGM report or meter app produces. Typing in this morning fasting reading gives a meaningless number and a label that can scare you for nothing. Anemia, hemoglobin variants, pregnancy and a recent transfusion all pull measured A1c away from the estimate. This is not a diagnosis. The math runs in your browser.