A1C to eAG (mg/dL)
The ADAG study regression formula converts A1C percentage to estimated average glucose. eAG = 28.7 × A1C - 46.7. For example, a 7% A1C equals an eAG of approximately 154 mg/dL.
Health
About A1C Calculator
Convert A1C to eAG, estimate A1C from readings, and check ADA risk bands.
A1C to eAGglucose logrisk bandsADA reference
About this calculator
What this does
Converts hemoglobin A1C percentages to estimated average glucose (eAG) in mg/dL or mmol/L using the ADAG study formula, estimates A1C from a log of fingerstick glucose readings, and classifies results into ADA risk categories: normal, prediabetes, or diabetes range.
Who it is for
People with diabetes or prediabetes who want to understand their A1C results, track their average glucose levels from home readings, and see where they fall on the ADA clinical risk scale. Also useful for caregivers and health-conscious individuals monitoring their metabolic health.
How it works
The Convert tab applies the formula eAG = 28.7 × A1C - 46.7 to translate an A1C lab result into an estimated average glucose level, and vice versa. The Glucose Log tab averages your entered fingerstick readings and estimates an A1C from the mean. The Risk Check tab classifies any A1C value into the appropriate ADA range and provides a clinical note.
Limitations
Estimated A1C from fingerstick readings is not a substitute for a laboratory HbA1c test. The ADAG formula is a population average and individual results may vary. Glucose logs assume evenly distributed readings and may not capture all daily fluctuations.
Formula
A1C to eAG (mmol/L)
The same conversion expressed in SI units for international use. eAG (mmol/L) = 1.594 × A1C - 2.594. A 7% A1C equals approximately 8.6 mmol/L.
eAG to A1C (Reverse)
Given an average glucose reading, estimate the corresponding A1C. A1C = (eAG + 46.7) / 28.7 for mg/dL, or A1C = (eAG + 2.594) / 1.594 for mmol/L.
Average Glucose from Log
Sum all glucose readings and divide by the count to find the mean, then apply the reverse ADAG formula to estimate A1C. avgGlucose = sum(readings) / count, estimatedA1C = (avgGlucose + 46.7) / 28.7
How it works
Step 1
Select your glucose unit
Toggle between mg/dL (US standard) and mmol/L (international standard) at the top of the calculator. All inputs and outputs will use your selected unit.
Step 2
Use the Convert tab
Enter an A1C percentage to see the equivalent estimated average glucose (eAG), or enter an eAG value to calculate the corresponding A1C. Results update live as you type.
Step 3
Log your glucose readings
Switch to the Glucose Log tab and add your fingerstick readings with measurement period tags (fasting, postprandial, bedtime). The calculator averages them and estimates your A1C from the log data.
Step 4
Check your risk category
Go to the Risk Check tab to see where your A1C falls on the ADA scale: Normal (< 5.7%), Prediabetes (5.7-6.4%), or Diabetes Range (≥ 6.5%). A clinical note provides context for each result.
Step 5
Review your results
Compare your estimated A1C from the glucose log against your lab-measured A1C. The risk check provides a visual category indicator with color coding and actionable clinical guidance.
Reference ranges
Normal Range
A1C below 5.7% (eAG below 117 mg/dL / 6.5 mmol/L). Fasting glucose 70-100 mg/dL (3.9-5.6 mmol/L). No diabetes diagnosis. Maintain healthy diet and exercise.
Prediabetes Range
A1C 5.7-6.4% (eAG 117-137 mg/dL / 6.5-7.6 mmol/L). Fasting glucose 100-125 mg/dL (5.6-6.9 mmol/L). Lifestyle changes can reduce progression risk to type 2 diabetes.
Diabetes Range
A1C 6.5% or higher (eAG 140 mg/dL / 7.8 mmol/L or above). Fasting glucose 126 mg/dL (7.0 mmol/L) or higher. Medical management and regular monitoring are recommended.
Glucose Variability
Post-meal glucose can rise to 140-180 mg/dL (7.8-10.0 mmol/L) even in non-diabetic individuals. Diabetes management targets often aim for postprandial peaks below 180 mg/dL (10.0 mmol/L).