HbA1c Calculator
Convert between HbA1c and estimated average glucose
Your History
What is HbA1c?
HbA1c (glycated hemoglobin) measures the percentage of hemoglobin in your blood that has glucose attached to it. It reflects your average blood sugar level over the past 2–3 months and is a key test for diagnosing and monitoring diabetes.
The ADAG Formula
This calculator uses the formula from the A1C-Derived Average Glucose (ADAG) study: eAG (mg/dL) = 28.7 × HbA1c − 46.7. This internationally recognized formula was established through a large multicenter study published in 2008.
eAG = 28.7 × HbA1c − 46.7 mg/dL
Understanding Your Results
Normal
Your blood sugar levels are within a healthy range. Maintain a balanced diet and regular exercise.
Prediabetes
Your blood sugar is higher than normal. Lifestyle changes can help prevent progression to type 2 diabetes.
Diabetes
This level indicates diabetes. Work with your healthcare provider to develop a management plan.
Frequently Asked Questions
How do you calculate A1C to average glucose?
Use the ADAG formula: eAG (mg/dL) = 28.7 × A1C − 46.7. For example, an A1C of 7.0% equals approximately 154 mg/dL (8.6 mmol/L). Use our calculator above for instant conversion.
What is a normal A1C level?
A normal A1C is below 5.7%, corresponding to an average blood glucose under 117 mg/dL (6.5 mmol/L). Between 5.7% and 6.4% indicates prediabetes, while 6.5% or higher indicates diabetes.
What does an A1C of 7 mean?
An A1C of 7.0% means your estimated average blood sugar over the past 2–3 months is about 154 mg/dL (8.6 mmol/L). This is the standard treatment target for most adults with diabetes.
Can anemia affect A1C results?
Yes. Iron deficiency anemia can falsely raise A1C by 0.4–0.7%, while hemolytic anemia can lower it. If your A1C doesn't match your meter readings, discuss with your doctor.
Further Reading
A1C Conversion Chart: HbA1c to Glucose Table
A1C conversion chart with HbA1c to glucose and glucose to A1C tables. Convert average glucose in mg/dL and mmol/L with diabetes risk ranges.
How to Calculate A1C — ADAG Formula Explained
How to calculate A1C from glucose and convert A1C to average blood sugar. The ADAG conversion formula explained with examples in mg/dL and mmol/L.
A1C Normal Range: 5.7%, 6.5%, Prediabetes and Diabetes
A1C normal range explained: below 5.7% is normal, 5.7–6.4% is prediabetes, and 6.5% or higher can indicate diabetes.
A1C and Anemia: Why Results Can Be Falsely High or Low
Anemia can make A1C falsely high or low. Learn why there is no universal A1C correction formula and how to compare eAG with CGM or meter averages.
A1C to Glucose — How to Convert A1C to Average Blood Sugar
Step-by-step A1C to glucose conversion with the ADAG formula. Quick reference table for A1C to eAG in mg/dL and mmol/L.