A1C and Average Blood Glucose Converter
Use this calculator to convert between your A1C percentage and your estimated average blood glucose (eAG) levels in both mg/dL and mmol/L. Enter a value in *one* of the fields below, and the calculator will provide the equivalent values.
Understanding A1C and Average Blood Glucose
The A1C test, also known as the hemoglobin A1c or HbA1c test, is a crucial blood test used to diagnose type 2 diabetes and prediabetes, and to monitor diabetes management. It measures your average blood sugar levels over the past two to three months. Unlike daily blood glucose readings, which show immediate sugar levels, A1C provides a longer-term picture of your glucose control.
When glucose (sugar) enters your bloodstream, it attaches to hemoglobin, a protein in your red blood cells. The more glucose in your blood, the more hemoglobin will be glycated (sugar-coated). The A1C test measures the percentage of your red blood cells that have sugar-coated hemoglobin. Since red blood cells live for about three months, the A1C test reflects your average blood sugar level during that period.
Estimated Average Glucose (eAG)
Estimated Average Glucose (eAG) is a term used to translate your A1C percentage into a unit that is more familiar to people who regularly monitor their blood sugar: mg/dL (milligrams per deciliter) or mmol/L (millimoles per liter). This conversion helps individuals understand their A1C result in the same units they see on their home blood glucose meters.
The formulas used for these conversions are based on extensive research and are widely accepted by medical professionals:
- From A1C to eAG (mg/dL): eAG (mg/dL) = 28.7 × A1C – 46.7
- From A1C to eAG (mmol/L): eAG (mmol/L) = 1.59 × A1C – 2.59
- From eAG (mg/dL) to A1C: A1C (%) = (eAG (mg/dL) + 46.7) / 28.7
- From eAG (mmol/L) to A1C: A1C (%) = (eAG (mmol/L) + 2.59) / 1.59
Interpreting Your A1C Results
Here's a general guide to A1C levels:
- Normal: Below 5.7% (eAG approx. 97 mg/dL or 5.4 mmol/L)
- Prediabetes: 5.7% to 6.4% (eAG approx. 117-137 mg/dL or 6.5-7.6 mmol/L)
- Diabetes: 6.5% or higher (eAG approx. 140 mg/dL or 7.8 mmol/L and above)
It's important to remember that these are general guidelines. Your target A1C level may vary based on your age, other health conditions, and individual circumstances. Always discuss your A1C results and treatment plan with your healthcare provider. This calculator is for informational purposes only and should not replace professional medical advice.
Example Conversions:
- An A1C of 5.0% corresponds to an eAG of approximately 97 mg/dL or 5.4 mmol/L.
- An A1C of 6.5% (diabetes diagnosis threshold) corresponds to an eAG of approximately 126 mg/dL or 7.0 mmol/L.
- An A1C of 8.0% corresponds to an eAG of approximately 154 mg/dL or 8.6 mmol/L.