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A1c Calculator: A1c to Average Glucose (eAG)
To convert A1c to estimated average glucose (eAG), use eAG in mg/dL = 28.7 × A1c − 46.7. An A1c of 7% equals an eAG of about 154 mg/dL (8.6 mmol/L), and 6% equals about 126 mg/dL. The calculator converts both directions, prints a conversion chart and shows the American Diabetes Association category for the A1c.
Prepared by Prospyr · Reviewed October 3, 2026 · Free, no sign-up, runs in your browser
NGSP percent, for example 7.0.
Estimated average glucose (eAG)
154mg/dL
A1c 7% is an average of 154 mg/dL (8.6 mmol/L).
ADA category for an A1c of 7%: In the diabetes range (6.5% or higher).
Decision support only; it does not replace clinical judgment. eAG is a statistical estimate; it is not the same as day-to-day readings.
A1c conversion chart
| A1c (%) | eAG (mg/dL) | eAG (mmol/L) |
|---|---|---|
| 4.0 | 68 | 3.8 |
| 4.5 | 82 | 4.6 |
| 5.0 | 97 | 5.4 |
| 5.5 | 111 | 6.2 |
| 6.0 | 125 | 7 |
| 6.5 | 140 | 7.8 |
| 7.0 | 154 | 8.6 |
| 7.5 | 169 | 9.4 |
| 8.0 | 183 | 10.2 |
| 8.5 | 197 | 10.9 |
| 9.0 | 212 | 11.7 |
| 9.5 | 226 | 12.5 |
| 10.0 | 240 | 13.3 |
| 10.5 | 255 | 14.1 |
| 11.0 | 269 | 14.9 |
| 11.5 | 283 | 15.7 |
| 12.0 | 298 | 16.5 |
| 12.5 | 312 | 17.3 |
| 13.0 | 326 | 18.1 |
| 13.5 | 341 | 18.9 |
| 14.0 | 355 | 19.7 |
A1c to eAG formula
eAG (mg/dL) = 28.7 × A1c − 46.7, and the reverse, A1c = (eAG + 46.7) ÷ 28.7.
This is the linear relationship reported by the A1c-Derived Average Glucose (ADAG) study. For mmol/L, divide mg/dL by 18.016 (glucose has a molar mass of 180.16 g/mol).
A1c conversion chart: common values
| A1c | eAG (mg/dL) | eAG (mmol/L) |
|---|---|---|
| 5% | 97 | 5.4 |
| 6% | 126 | 7.0 |
| 7% | 154 | 8.6 |
| 8% | 183 | 10.2 |
| 9% | 212 | 11.7 |
| 10% | 240 | 13.3 |
The tool above has a full chart in half-percent steps from 4% to 14% that you can print.
ADA A1c categories
| Category | A1c |
|---|---|
| Below the prediabetes range | Below 5.7% |
| Prediabetes range | 5.7% to 6.4% (39 to 47 mmol/mol) |
| Diabetes range | 6.5% or higher (48 mmol/mol or higher) |
These thresholds are from Section 2 of the ADA Standards of Care in Diabetes 2026 and apply to a measured A1c, not to an eAG. Diagnosis in the absence of unequivocal hyperglycemia requires two abnormal results.
Using it in a practice
Weight-management and metabolic programs often track A1c over time next to other labs. Prospyr's analytics covers practice-level reporting, and charting keeps lab notes with the patient record. For other lab math, try the HOMA-IR calculator.
Frequently asked questions
How do I convert A1c to average glucose?
Multiply the A1c percentage by 28.7 and subtract 46.7 to get eAG in mg/dL. For 7.0%, that is 28.7 × 7 − 46.7 = 154.2 mg/dL. Divide by 18.016 for mmol/L, which gives 8.6.
How do I convert glucose to A1c?
Add 46.7 to the average glucose in mg/dL and divide by 28.7. An average of 154 mg/dL gives (154 + 46.7) ÷ 28.7 = 7.0%. For mmol/L, multiply by 18.016 first.
What is eAG?
eAG is estimated average glucose, a way of expressing an A1c in the same units as meter readings. The relationship comes from the ADAG study (Nathan and colleagues, Diabetes Care, 2008), which compared A1c with continuous and frequent glucose measurements.
What A1c is prediabetes or diabetes?
The ADA Standards of Care 2026 list an A1c of 5.7% to 6.4% (39 to 47 mmol/mol) as the prediabetes range and 6.5% or higher (48 mmol/mol or higher) as the diabetes range. In the absence of unequivocal hyperglycemia, diagnosis needs two abnormal results.
Why doesn't my meter average match my eAG?
eAG is a statistical estimate from a population, so one person's meter average can differ from it. Meter readings may also miss overnight and after-meal values. The calculator gives the published relationship, not a prediction for an individual.
Does this tell me whether a patient has diabetes?
No. It converts units and shows the published ADA ranges. A diagnosis follows the ADA criteria and clinical judgment of the treating provider.
Sources and scope
- Nathan DM et al. Translating the A1C assay into estimated average glucose values. Diabetes Care 2008;31:1473-8
Peer-reviewed. The ADAG relationship eAG = 28.7 × A1C − 46.7.
- American Diabetes Association. 2. Diagnosis and Classification of Diabetes: Standards of Care in Diabetes-2026. Diabetes Care 2026;49(Suppl 1):S27-S49
A1C thresholds for prediabetes (5.7% to 6.4%) and diabetes (6.5% or higher).
Decision support only; it does not replace clinical judgment. The tool converts units with the published ADAG relationship and quotes ADA ranges. It does not diagnose or recommend treatment or glucose targets.