How to Use the HbA1c to Glucose Converter
Hemoglobin A1c (HbA1c) measures the percentage of hemoglobin in red blood cells that has glucose attached, reflecting your average blood sugar over the past 2-3 months rather than a single snapshot. This calculator applies the American Diabetes Association's official formula, eAG (mg/dL) = 28.7 x HbA1c(%) - 46.7, to convert your HbA1c into an estimated average glucose (eAG).
The converted result is shown in both mg/dL and mmol/L. Per ADA guidelines, an HbA1c below 5.7% is considered normal, 5.7-6.4% falls into prediabetes, and 6.5% or higher is in the diabetes range. Because it reflects a longer-term average rather than a single fingerstick reading, HbA1c is a useful complement to day-to-day glucose monitoring.
Keep in mind this is a reference conversion and not a medical diagnosis. Actual diabetes diagnosis considers fasting glucose and oral glucose tolerance testing together, and conditions like anemia or certain blood disorders can make HbA1c readings diverge from true glucose levels. Always confirm your results with a physician.
Frequently Asked Questions
We use the American Diabetes Association (ADA) formula: eAG (mg/dL) = 28.7 x HbA1c(%) - 46.7. This approximates your average blood glucose over the past 2-3 months.
This calculator is a reference conversion tool only. Under ADA criteria, an HbA1c of 6.5% or higher suggests diabetes, but confirmation requires repeat testing and a physician's overall assessment.