HbA1c to average blood sugar
HbA1c shows your average blood sugar over the past two to three months. Enter an HbA1c percentage to see the estimated average glucose (eAG) it corresponds to, or enter an average glucose to see the matching HbA1c.
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HbA1c ranges
| HbA1c | Meaning (ADA) | Average glucose |
|---|---|---|
| Below 5.7% | Normal | below about 117 mg/dL |
| 5.7% to 6.4% | Prediabetes | about 117 to 137 mg/dL |
| 6.5% or more | Diabetes range (confirm with a repeat test) | about 140 mg/dL or more |
How it's calculated
The ADAG study formula: average glucose (mg/dL) = 28.7 × HbA1c − 46.7, or in mmol/L = 1.59 × HbA1c − 2.59. Anaemia, recent blood loss or transfusion, pregnancy, kidney disease and some haemoglobin variants can make HbA1c misleading; your doctor reads it with those in mind.
Frequently asked questions
What is a normal HbA1c?
Below 5.7%. 5.7% to 6.4% is prediabetes and 6.5% or more is in the diabetes range.
HbA1c 7 means what blood sugar?
An HbA1c of 7% corresponds to an estimated average glucose of about 154 mg/dL (8.6 mmol/L).
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Keep your reports in CuraVaultLast updated 03 November 2026.