A1C Calculator
Convert A1C to average blood glucose.
Enter your values
Enter the a1c in %.
Enter the or average glucose in mg/dL.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Estimated average glucose
- 148.5 mg/dL
- A1C
- 6.8%
- In mmol/L
- 8.24
- Category
- Diabetes range
- IFCC units
- 50.8 mmol/mol
Quick answer
A1C reflects average blood glucose over about three months; eAG (mg/dL) = 28.7 × A1C − 46.7.
eAG = 28.7 × A1C − 46.7
At a glance
| What it does | Convert A1C to average blood glucose. |
|---|---|
| Category | Health |
| Inputs needed | A1C, Or average glucose |
| Formula | eAG = 28.7 × A1C − 46.7 |
| Cost | Free — no sign-up, no download |
How to use the A1C Calculator
- 1Enter your A1C percentage from your lab report.
- 2Or enter an average glucose to work backwards.
- 3Compare against the normal, prediabetes and diabetes ranges.
Inputs explained
- A1C(%)
- Enter the a1c in %.
- Or average glucose(mg/dL)
- Enter the or average glucose in mg/dL.
Frequently asked questions
What A1C is normal?
Below 5.7%; 5.7–6.4% is prediabetes and 6.5% or above indicates diabetes.
How often should A1C be tested?
Every 3–6 months for people managing diabetes.
What do I need to enter into the A1C Calculator?
Just 2 values: a1c, or average glucose. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the A1C Calculator work out the answer?
A1C reflects average blood glucose over about three months; eAG (mg/dL) = 28.7 × A1C − 46.7. It applies the formula eAG = 28.7 × A1C − 46.7 and shows the working so you can check each step by hand.
Is the A1C Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.