Convert
The full table
| A1C | eAG mg/dL | eAG mmol/L |
|---|---|---|
| 5.0% | 97 | 5.4 |
| 5.5% | 111 | 6.2 |
| 6.0% | 126 | 7.0 |
| 6.5% | 140 | 7.7 |
| 7.0% | 154 | 8.5 |
| 7.5% | 169 | 9.3 |
| 8.0% | 183 | 10.1 |
| 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 |
How to read the result
An A1C is a percentage: the share of your hemoglobin that has glucose attached. Because red cells live about three months, the percentage tracks average blood glucose over roughly that window, with the most recent weeks weighing more than the earliest ones. The estimated average glucose (eAG) on the right of the table is the same information translated into the unit a glucose meter shows, mg/dL, the US unit, or mmol/L. Nothing is gained or lost in the translation; it exists so a reader can compare an A1C with the fasting or post-meal numbers they already know.
The American Diabetes Association's diagnostic cutoffs are set on the A1C, not the eAG: below 5.7 percent is normal, 5.7 to 6.4 percent is prediabetes, and 6.5 percent or above is diabetes, on a laboratory test in a nonpregnant adult, confirmed by a second measurement unless symptoms are clear. Those thresholds and the rows above them are laid out with their source on the hemoglobin A1C reference page, and What your A1C means covers what to do at each level.
When the number misleads
The A1C assumes red cells with a normal lifespan and ordinary hemoglobin. NIDDK's A1C test page (last reviewed April 2018) lists what breaks that assumption: iron-deficiency anemia can produce a falsely high result; conditions that change red-cell lifespan, such as recent blood loss, sickle cell disease, erythropoietin treatment, hemodialysis or transfusion, can change A1C levels; kidney failure and liver disease are other causes of false results; and some hemoglobin variants interfere with some A1C tests. NIDDK says a clinician may suspect interference when your A1C and your blood glucose results do not match, and the fasting plasma glucose test and the oral glucose tolerance test are the other ways to diagnose diabetes. The eAG from this converter inherits every one of the A1C's blind spots. If your report carries a flag about a hemoglobin variant, treat the converted number as unreliable until a clinician says otherwise.
Where the equation comes from
The A1C-Derived Average Glucose (ADAG) study fitted continuous glucose monitoring and self-testing data against laboratory A1C in 507 adults and derived eAG(mg/dL) = 28.7 × A1C − 46.7. The ADA adopted it for the eAG values on lab reports. It is an estimate: two people with the same A1C can have meaningfully different averages, and conditions that change red-cell lifespan (anemia, kidney disease, pregnancy, hemoglobin variants) shift A1C itself.
A converter is not a diagnosis. Diagnosing diabetes takes a laboratory A1C on a DCCT-certified method, confirmed, read by a clinician.