A1c to eAG Calculator

Convert Average Blood Glucose to HbA1c and vice versa

Convert Blood Glucose (eAG) to A1c

Estimated Average Glucose (mg/dL):

Your Estimated A1c is:
—%

Convert A1c to Blood Glucose (eAG)

A1c Percentage (%):

Your Estimated Average Glucose is:
— mg/dL

How is A1c Calculated?

The Hemoglobin A1c (HbA1c) test measures your average blood sugar levels over the past 2 to 3 months. Unlike a daily finger-prick test which shows your blood sugar at a single moment, the A1c provides a "big picture" of your glucose control.

The ADAG Formula

The relationship between your A1c and your Estimated Average Glucose (eAG) is determined by a specific mathematical formula derived from the A1c-Derived Average Glucose (ADAG) study. This study established the following linear equation:

            eAG (mg/dL) = (28.7 × A1c) – 46.3
        

To reverse this calculation and find your A1c based on your average daily readings, the formula is:

            A1c = (eAG + 46.3) / 28.7
        

A1c Chart and Interpretations

Health organizations typically categorize A1c levels as follows:

A1c Level	Avg. Glucose (mg/dL)	Category
Below 5.7%	Below 117 mg/dL	Normal
5.7% to 6.4%	117 – 137 mg/dL	Prediabetes
6.5% or higher	140+ mg/dL	Diabetes

Why Use eAG?

The Estimated Average Glucose (eAG) translates your A1c percentage into the same units (mg/dL) that you see on your daily glucose meter or Continuous Glucose Monitor (CGM). This makes it easier to understand how your laboratory A1c test relates to your day-to-day blood sugar monitoring.

Note: While this calculator is based on clinically accepted formulas, it should not replace medical advice. Always consult with your doctor regarding your A1c results and diabetes management plan.