HbA1c Chart: Normal, Prediabetes and Diabetes Ranges Explained

HbA1c (glycated haemoglobin) reflects your average blood sugar over the past 2–3 months, which is why doctors trust it more than a single fasting reading for diagnosing and monitoring diabetes.

Standard HbA1c cutoffs

• Normal: below 5.7%
• Prediabetes: 5.7% – 6.4%
• Diabetes: 6.5% or above (confirmed on a repeat test)
• Common treatment target for most diabetics: below 7% — individualised by your doctor

HbA1c to average blood sugar

Each HbA1c point maps to an estimated average glucose: 6% ≈ 126 mg/dL, 7% ≈ 154 mg/dL, 8% ≈ 183 mg/dL, 9% ≈ 212 mg/dL. A falling HbA1c means your last few months genuinely improved — it can't be gamed by one careful day before the test.

How often should you test?

If you have diabetes: every 3 months until stable, then every 6 months. If you're prediabetic: every 6 months alongside lifestyle changes. Everyone over 35, or anyone overweight with a family history: once a year. No fasting is required for HbA1c.

Note: anaemia, recent blood loss and haemoglobin disorders can skew HbA1c slightly — your doctor may pair it with a fasting glucose for a fuller picture.