Convert an A1C result into estimated average glucose (eAG) in mg/dL and mmol/L. See where the result falls in the American Diabetes Association ranges. Free, private, and runs entirely in your browser.
A1C reflects the average blood glucose over roughly the past two to three months. The ADAG study found a linear relationship between A1C and average glucose, which gives the eAG formula.
What A1C is normal? Below 5.7% is normal. 5.7% to 6.4% is prediabetes and 6.5% or higher is in the diabetes range, according to the ADA.
What average glucose is an A1C of 7%? About 154 mg/dL, or 8.6 mmol/L.
An A1C of 7% gives eAG = 28.7 × 7 − 46.7 = 154.2 mg/dL, which is 154.2 ÷ 18.016 ≈ 8.6 mmol/L. An A1C of 6% gives about 126 mg/dL.
Why does my meter average differ from eAG? Meters sample only some moments of the day, while A1C reflects the whole period, so the numbers often differ.
How often is A1C tested? Often every three to six months for people with diabetes, as advised by a clinician.
Samuel Rahbar and colleagues identified the raised level of hemoglobin A1c in people with diabetes in 1968. The A1c-Derived Average Glucose (ADAG) study, published in 2008, established the linear relationship between A1C and average glucose that gave rise to the eAG formula, and it allows A1C results to be expressed in the same units as home glucose meters.
Use this calculator to make sense of an A1C result in glucose units. This is general information, not medical advice. Talk to a doctor or other qualified professional about your own results.
Can A1C be too low? Very low values can occur with certain conditions or medications and should be discussed with a clinician.
What is the difference between A1C and fasting glucose? Fasting glucose is a single moment, while A1C averages several months.