A1C from Estimated Average Glucose (eAG) Calculator
Use this calculator to estimate your A1C percentage based on your Estimated Average Glucose (eAG) level.
Understanding A1C and Estimated Average Glucose (eAG)
The A1C test, also known as the hemoglobin A1C or HbA1c test, is a crucial blood test for managing and diagnosing diabetes. It provides an average of your blood glucose (sugar) levels over the past two to three months. Unlike daily blood glucose readings, which show your sugar level at a specific moment, A1C offers a broader picture of your glucose control.
What is A1C?
Hemoglobin is a protein found in red blood cells that carries oxygen throughout your body. When glucose enters your bloodstream, it attaches to hemoglobin. This process is called glycation. The more glucose in your blood, the more it attaches to hemoglobin. The A1C test measures the percentage of hemoglobin that is glycated. Since red blood cells live for about three months, the A1C test reflects your average blood glucose levels over that period.
- Normal A1C: Below 5.7%
- Pre-diabetes: 5.7% to 6.4%
- Diabetes: 6.5% or higher
What is Estimated Average Glucose (eAG)?
Estimated Average Glucose (eAG) is a term used to translate your A1C test result into a unit (mg/dL or mmol/L) that is more familiar to people who regularly monitor their blood glucose. It represents the average daily blood glucose level that corresponds to a given A1C percentage. This can help individuals better understand what their A1C result means in terms of their day-to-day glucose levels.
The Relationship Between A1C and eAG
The relationship between A1C and eAG is based on a formula derived from studies that compared A1C results with average glucose levels obtained from frequent blood glucose monitoring. The formula used to convert A1C to eAG (and vice-versa) is:
- eAG (mg/dL) = (28.7 × A1C) – 46.7
- A1C (%) = (eAG + 46.7) / 28.7
This calculator uses the second formula to estimate your A1C based on an eAG value you provide. If your eAG is in mmol/L, it will first be converted to mg/dL (1 mmol/L = 18.0182 mg/dL) before applying the formula.
Why is A1C Important?
Monitoring A1C levels is vital for several reasons:
- Diagnosis: It's one of the primary tests used to diagnose pre-diabetes and type 1 and type 2 diabetes.
- Management: For people with diabetes, A1C helps healthcare providers assess how well their treatment plan is working and make necessary adjustments to medication, diet, or exercise.
- Risk Assessment: Maintaining A1C levels within a target range significantly reduces the risk of developing diabetes-related complications such as heart disease, kidney disease, nerve damage, and eye problems.
Realistic Examples:
- If your eAG is 126 mg/dL (7.0 mmol/L), your estimated A1C would be approximately 6.0%, indicating pre-diabetes.
- If your eAG is 154 mg/dL (8.5 mmol/L), your estimated A1C would be approximately 7.0%, which is a common target for many individuals with diabetes.
- If your eAG is 200 mg/dL (11.1 mmol/L), your estimated A1C would be approximately 8.6%, suggesting that blood glucose levels may need better management.
Always discuss your A1C results and eAG with your healthcare provider to understand what they mean for your health and treatment plan.