A1C Converter

Free A1C converter: turn HbA1c in % or mmol/mol into estimated average glucose in mg/dL or mmol/L and back, with the ADA ranges and a full table.

β€”A1C (%)
β€”A1C (mmol/mol, IFCC)
β€”Average glucose (mg/dL)
β€”Average glucose (mmol/L)

ADA range:

Glucose: mg/dL ↔ mmol/L

ADA fasting glucose ranges: below 100 mg/dL (5.6 mmol/L) is normal, 100–125 mg/dL (5.6–6.9 mmol/L) is prediabetes, and 126 mg/dL (7.0 mmol/L) or above is in the diabetes range.

This is a conversion, not a diagnosis. Diabetes is diagnosed by a doctor from laboratory tests, and A1C can read high or low with anaemia, kidney disease, pregnancy or some haemoglobin variants.

Conversion table

A1C %mmol/molmg/dLmmol/L

Also: Blood Sugar Converter (mg/dL to mmol/L) Β· BMI Calculator

What it does

The A1C (HbA1c) test measures the share of haemoglobin with glucose attached, which reflects the average blood sugar over the last two to three months. The ADAG study turned it into an estimated average glucose: eAG (mg/dL) = 28.7 × A1C − 46.7, so 7% is about 154 mg/dL (8.6 mmol/L). Laboratories outside the USA often report A1C in mmol/mol (IFCC units), where 7% is 53 mmol/mol.

How to use it

  1. Choose what you have: A1C in % or mmol/mol, or an average glucose in mg/dL or mmol/L.
  2. Type the value; the other three units and the ADA range appear at once.
  3. Use the table for a quick look-up, or the glucose converter for a single reading.

The arithmetic runs in your browser. Nothing you type is sent anywhere and nothing is stored, so you can use these with real numbers.

Frequently asked questions

What is a normal A1C?
Below 5.7% (39 mmol/mol) is normal, 5.7% to 6.4% (39–46 mmol/mol) indicates prediabetes and 6.5% (48 mmol/mol) or above is in the diabetes range. For many people with diabetes, the ADA suggests a target below 7%, set individually with a doctor.

Why is my meter’s average different from the estimate?
A meter averages only the moments you test, often before meals, while A1C reflects every hour of the last months. The ADAG formula is also an average across many people, so an individual can differ by around 15–20 mg/dL.

Wikipedia — Glycated hemoglobin
American Diabetes Association — eAG calculator