HbA1c Calculator
Turn an HbA1c report into average blood sugar you can relate to — and back.
Understand your report.
Enter your HbA1c percentage.
How to use this tool
Enter the HbA1c percentage from your lab report. The tool shows the estimated average glucose (eAG) over the last 2–3 months.
Good to know
It uses the ADAG study formula used by the American Diabetes Association: eAG (mg/dL) = 28.7 × HbA1c − 46.7.
Step by step
- Choose whether you have an HbA1c % or an average blood sugar.
- Enter the value from your report or glucometer average.
- Tap Convert to see eAG in mg/dL and mmol/L, IFCC units and the range.
HbA1c to average blood sugar chart
| HbA1c (%) | IFCC (mmol/mol) | Average glucose (mg/dL) | Average glucose (mmol/L) |
|---|---|---|---|
| 5 | 31 | 97 | 5.4 |
| 5.7 | 39 | 117 | 6.5 |
| 6 | 42 | 126 | 7.0 |
| 6.5 | 48 | 140 | 7.8 |
| 7 | 53 | 154 | 8.6 |
| 8 | 64 | 183 | 10.2 |
| 9 | 75 | 212 | 11.8 |
| 10 | 86 | 240 | 13.4 |
| 11 | 97 | 269 | 14.9 |
| 12 | 108 | 298 | 16.5 |
What the ranges mean
- Below 5.7% — normal range.
- 5.7% to 6.4% — prediabetes range; lifestyle changes can help.
- 6.5% or above — diabetes range (a doctor confirms diagnosis, usually with a repeat test).
- For many adults with diabetes a target around 7% is common, but your doctor may set a different goal.
Why HbA1c matters
HbA1c measures how much glucose is attached to haemoglobin in red blood cells. Because these cells live about three months, HbA1c reflects your average blood sugar over the past 2–3 months — unlike a fasting test, which shows one moment. Conditions such as anaemia, recent blood loss, pregnancy or some haemoglobin variants can make HbA1c less reliable, which is why doctors look at it together with other tests.
Track related numbers with the BMI calculator (with Asian-Indian cut-offs) and the water intake calculator.
Frequently asked questions
What is a normal HbA1c level?
Below 5.7%. 5.7–6.4% is the prediabetes range and 6.5% or higher is in the diabetes range.
What average blood sugar is HbA1c 7%?
About 154 mg/dL (8.6 mmol/L), using eAG = 28.7 × 7 − 46.7.
How do I convert mmol/L to mg/dL?
Multiply mmol/L by 18 (18.016 precisely). 7.8 mmol/L ≈ 140 mg/dL.
Can this tool diagnose diabetes?
No. It converts numbers for understanding. Diagnosis and treatment decisions must come from a doctor.