An A1C conversion chart turns your A1C percentage into an estimated average glucose (eAG) expressed in mg/dL or mmol/L — the same units your home meter or continuous glucose monitor uses. This page gives a full chart from 4.0% to 14.0% in 0.1% steps, the math behind it, and tips on how to use it.
The A1C Conversion Formula
The American Diabetes Association uses a formula derived from a 2008 ADAG study:
eAG (mg/dL) = 28.7 × A1C − 46.7
For mmol/L: eAG (mmol/L) = 1.59 × A1C − 2.59 (or multiply mg/dL by 0.0555).
Example: A1C of 6.5% → (28.7 × 6.5) − 46.7 = 140 mg/dL, or 7.8 mmol/L.
Need a live calculator? See our A1C calculator.
Full A1C to eAG Conversion Chart
All values rounded to the nearest whole number for mg/dL and one decimal for mmol/L.
| A1C (%) | eAG (mg/dL) | eAG (mmol/L) | Category |
|---|---|---|---|
| 4.0 | 68 | 3.8 | Normal (low) |
| 4.5 | 82 | 4.6 | Normal |
| 5.0 | 97 | 5.4 | Normal |
| 5.1 | 100 | 5.5 | Normal |
| 5.2 | 103 | 5.7 | Normal |
| 5.3 | 105 | 5.9 | Normal |
| 5.4 | 108 | 6.0 | Normal |
| 5.5 | 111 | 6.2 | Normal |
| 5.6 | 114 | 6.3 | Normal (upper) |
| 5.7 | 117 | 6.5 | Prediabetes |
| 5.8 | 120 | 6.7 | Prediabetes |
| 5.9 | 123 | 6.8 | Prediabetes |
| 6.0 | 126 | 7.0 | Prediabetes |
| 6.1 | 128 | 7.1 | Prediabetes |
| 6.2 | 131 | 7.3 | Prediabetes |
| 6.3 | 134 | 7.4 | Prediabetes |
| 6.4 | 137 | 7.6 | Prediabetes (upper) |
| 6.5 | 140 | 7.8 | Diabetes |
| 6.6 | 143 | 7.9 | Diabetes |
| 6.7 | 146 | 8.1 | Diabetes |
| 6.8 | 148 | 8.2 | Diabetes |
| 6.9 | 151 | 8.4 | Diabetes |
| 7.0 | 154 | 8.6 | Diabetes (ADA target) |
| 7.5 | 169 | 9.4 | Diabetes |
| 8.0 | 183 | 10.2 | Diabetes |
| 8.5 | 197 | 10.9 | Diabetes |
| 9.0 | 212 | 11.8 | Diabetes |
| 9.5 | 226 | 12.6 | Diabetes |
| 10.0 | 240 | 13.4 | Uncontrolled |
| 10.5 | 255 | 14.1 | Uncontrolled |
| 11.0 | 269 | 14.9 | Uncontrolled |
| 11.5 | 283 | 15.7 | Uncontrolled |
| 12.0 | 298 | 16.5 | Uncontrolled |
| 12.5 | 312 | 17.3 | Uncontrolled |
| 13.0 | 326 | 18.1 | Uncontrolled |
| 13.5 | 341 | 18.9 | Uncontrolled |
| 14.0 | 355 | 19.7 | Very uncontrolled |
How to Read the Chart
Find your A1C in the left column, then read across:
- mg/dL column — standard U.S. glucose meter units.
- mmol/L column — standard units in the U.K., Canada, Australia, and most of the world.
- Category column — how the ADA classifies that A1C.
A1C Diagnostic Cutoffs
| A1C Range | Diagnosis |
|---|---|
| Below 5.7% | Normal |
| 5.7% – 6.4% | Prediabetes |
| 6.5% or higher | Diabetes (requires confirmation) |
See our detailed A1C chart article for context on each range, and our normal A1C guide for typical values by age.
Why A1C and Daily Readings Don’t Always Match
The conversion chart shows the average glucose your A1C represents, but daily numbers swing above and below that average. A person with an A1C of 6.0% (eAG 126 mg/dL) might see fasting readings of 95 mg/dL and post-meal readings of 170 mg/dL. Both can be consistent with the same A1C.
Factors that can make A1C and meter numbers disagree:
- Anemia, recent blood loss, or blood transfusion
- Kidney disease or liver disease
- Pregnancy
- Hemoglobin variants (more common in people of African, Mediterranean, or Southeast Asian descent)
- Recent illness or steroid use
If your A1C and meter readings consistently disagree, ask your clinician about alternative tests like fructosamine or a continuous glucose monitor.
How Often to Test A1C
| Status | Recommended Frequency |
|---|---|
| No risk factors, adult | Every 3 years starting at 35 |
| Overweight + 1 risk factor | Every 1-3 years |
| Prediabetes | Every year |
| Diabetes, stable | Every 6 months |
| Diabetes, changing treatment | Every 3 months |
How to Lower a High A1C
A1C reflects about 3 months of average glucose, with the most recent 4 weeks weighted most heavily. If your number is in the prediabetes or diabetes range, lifestyle changes can move it meaningfully in 8-12 weeks:
- Lose 5-7% of body weight
- Walk or exercise at least 150 minutes per week
- Cut refined carbs and sugar-sweetened drinks
- Prioritize sleep (7-9 hours)
- Consider metformin if prescribed
On average, lifestyle change lowers A1C by 0.3 to 1.0 percentage points, and metformin adds another 0.5 to 1.0.
The Bottom Line
The A1C conversion chart bridges your long-term average (a lab test) and your everyday meter numbers. Memorize the anchor points — 5.7% ≈ 117 mg/dL, 6.5% ≈ 140 mg/dL, 7.0% ≈ 154 mg/dL — and the rest is easy arithmetic with the ADA formula. Use it alongside your daily readings, and talk with your clinician about the target that is right for your age, health, and goals.
