How do I convert A1C to estimated average glucose?
Use eAG (mg/dL) = 28.7 × A1C (%) − 46.7. Divide that result by 18 for eAG in mmol/L. For example, A1C of 7% gives about 154 mg/dL or 8.6 mmol/L.
Convert A1C (HbA1c) to estimated average glucose (eAG), or convert an average glucose value back to an A1C estimate, in mg/dL or mmol/L.
Free to use, with no sign-up. An educational estimate, not a diagnosis or a replacement for a lab test.
This calculator uses the equation published by the ADA. Estimates do not replace measured glucose or clinical advice. Results are for informational purposes only—consult your healthcare provider for medical advice.
A1C shows your average blood sugar over the past 2–3 months.
A1C reference ranges:
eAG converts your A1C into the same units used on your glucose meter.
This tool is for educational use only. Follow guidance from your healthcare provider for all medical decisions.
The American Diabetes Association conversion tool publishes the A1C-Derived Average Glucose (ADAG) equation used here:
Example: 28.7 × 7 − 46.7 = 154.2 mg/dL, displayed as 154 mg/dL and 8.6 mmol/L. Calculations keep full precision before rounding the display.
| A1C (%) | eAG (mg/dL) | eAG (mmol/L) |
|---|---|---|
| 6% | 126 mg/dL | 7.0 mmol/L |
| 6.5% | 140 mg/dL | 7.8 mmol/L |
| 7% | 154 mg/dL | 8.6 mmol/L |
| 8% | 183 mg/dL | 10.2 mmol/L |
| 9% | 212 mg/dL | 11.8 mmol/L |
| 10% | 240 mg/dL | 13.4 mmol/L |
Values are rounded to whole mg/dL and one decimal place for mmol/L. Use the calculator above for other values.
Use eAG (mg/dL) = 28.7 × A1C (%) − 46.7. Divide that result by 18 for eAG in mmol/L. For example, A1C of 7% gives about 154 mg/dL or 8.6 mmol/L.
Use estimated A1C (%) = (average glucose in mg/dL + 46.7) ÷ 28.7. For mmol/L, multiply the average by 18 first. An average of 154 mg/dL gives an estimated A1C of about 7.0%.
A1C, also called HbA1c, reflects average blood glucose over roughly three months. Estimated average glucose (eAG) expresses the A1C-based estimate in mg/dL or mmol/L, the units used by glucose meters.
An A1C of 7% corresponds to an estimated average glucose of about 154 mg/dL (8.6 mmol/L). This average is not a target for every individual reading.
No. One fasting, after-meal, or random glucose reading is not a long-term average. Enter an average glucose value for the reverse estimate; this conversion does not replace a laboratory A1C test.
For glucose, divide mg/dL by 18 to estimate mmol/L; multiply mmol/L by 18 to estimate mg/dL. These are glucose units. This calculator accepts A1C as a percentage, not HbA1c in mmol/mol.
The equation estimates a population relationship, not an exact personal match. Averages also hide highs and lows. Changes in red blood cells, some hemoglobin variants, and certain health conditions can affect A1C. Discuss mismatches with your healthcare professional.
No. It converts values for education and does not diagnose diabetes, recommend medication doses, or choose a personal glucose target. Ask your healthcare professional to interpret your results.
A1C input accepts 4–20%. Average glucose input accepts 70–600 mg/dL or 3.9–33.3 mmol/L. These software input limits are not healthy ranges or treatment targets.
The calculator is free and runs calculations in your browser without an account. Sharing is optional. A shared link includes readable calculation values; anyone with the link can access them. Email, social, and AI destinations can receive the values you choose to send. Review the destination preview before continuing.
Learn more in our A1C and glucose resources, calculator tips, and privacy policy.
Created by Richard Crane. Content updated . Educational information, not medical advice. Listing these sources does not imply endorsement or clinical review of this calculator.