Estimate your A1C level based on your average blood glucose readings.
Estimated A1C Level
What is A1C and How is it Calculated?
The Hemoglobin A1C test (also known as HbA1c) is a blood test that provides information about a person's average blood sugar (glucose) levels over the past 2 to 3 months. It's a crucial tool for diagnosing and managing diabetes. Unlike a standard blood glucose test, which measures glucose at a single point in time, the A1C test reflects long-term glucose control.
How it Works: Glucose in your bloodstream attaches to hemoglobin, a protein in your red blood cells that carries oxygen. The more glucose there is in your blood, the more hemoglobin it attaches to. The A1C test measures the percentage of hemoglobin that has glucose attached to it.
This calculator provides an *estimation* of your A1C based on your reported average blood glucose. It uses a widely accepted conversion formula.
The Calculation Formula:
The most common formula used to estimate A1C from average blood glucose (in mg/dL) is:
A1C (%): Your estimated Hemoglobin A1C percentage.
Average Glucose (mg/dL): The average of your blood glucose readings, typically measured in milligrams per deciliter (mg/dL).
0.0248: A conversion factor.
4.45: A baseline constant.
The 'Frequency of Readings' input is included for context and to simulate a more thorough averaging process if you had many readings. While it doesn't directly alter this specific formula, it's good practice to have a consistent number of readings to establish a reliable average.
Interpreting Your Estimated A1C Results:
While this calculator provides an estimate, actual A1C levels should be confirmed with a healthcare professional. General interpretations include:
Below 5.7%: Considered normal.
5.7% to 6.4%: Prediabetes range.
6.5% or higher: Diabetes diagnosis.
Disclaimer: This calculator is for informational and estimation purposes only. It does not constitute medical advice. Always consult with your doctor or a qualified healthcare provider for diagnosis, treatment, and management of diabetes or any other health condition.
function calculateA1C() {
var avgGlucoseInput = document.getElementById("averageGlucose");
var frequencyInput = document.getElementById("frequency");
var resultDiv = document.getElementById("result");
var resultValueDiv = document.getElementById("result-value");
var resultUnitP = document.getElementById("result-unit");
var avgGlucose = parseFloat(avgGlucoseInput.value);
var frequency = parseFloat(frequencyInput.value); // Used for context, not calculation here
// Input validation
if (isNaN(avgGlucose) || avgGlucose <= 0) {
alert("Please enter a valid average blood glucose level (a positive number).");
resultDiv.style.display = 'none';
return;
}
if (isNaN(frequency) || frequency <= 0) {
alert("Please enter a valid frequency of readings (a positive number).");
resultDiv.style.display = 'none';
return;
}
// A1C calculation formula
var a1cEstimate = (avgGlucose * 0.0248) + 4.45;
// Display the result
resultValueDiv.textContent = a1cEstimate.toFixed(1); // Display with one decimal place
resultUnitP.textContent = "%";
resultDiv.style.display = 'block';
}