A1C
5.7 %
estimatea1c.com / A1C 5.7
An A1C of 5.7% corresponds to an estimated average glucose of about 117 mg/dL (6.5 mmol/L). It's also the first value in the American Diabetes Association's prediabetes range (5.7–6.4%) — one tenth of a point lower and you'd be classified normal.
A1C reflects your average blood glucose over roughly the past three months. At 5.7% you do not have diabetes, and your average glucose is only modestly above the population's healthy band. What the number signals is direction: insulin resistance typically builds for years before glucose rises, and 5.7 is often the first visible sign.
Keep one caveat in mind: lab A1C has a real margin of error (±0.1–0.2 points is common between labs and draws), and 5.7 sits right on a boundary. A single 5.7 is a prompt to re-test and pay attention — not a diagnosis of anything.
This is the stage where lifestyle change has its strongest evidence. In the landmark Diabetes Prevention Program, people with prediabetes who lost 5–7% of body weight and did ~150 minutes of moderate activity per week cut their risk of progressing to type 2 diabetes by 58% — better than metformin managed in the same trial. Sleep, resistance training, and cutting liquid sugar all pull the same direction.
Most clinicians recheck A1C at this level every 6–12 months. Tracking a periodic fasting glucose or logging readings between tests shows you the trend long before the next lab draw.
| A1C (%) | eAG (mg/dL) | eAG (mmol/L) | IFCC (mmol/mol) |
|---|---|---|---|
| 5.4% | 108 | 6.0 | 36 |
| 5.5% | 111 | 6.2 | 37 |
| 5.6% | 114 | 6.3 | 38 |
| 5.7% | 117 | 6.5 | 39 |
| 5.8% | 120 | 6.6 | 40 |
| 5.9% | 123 | 6.8 | 41 |
| 6.0% | 125 | 7.0 | 42 |
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Yes — 5.7% is the lowest value in the ADA prediabetes range (5.7–6.4%). But it sits right on the boundary and lab variability is real, so a repeat test is reasonable before acting on it.
About 117 mg/dL, or 6.5 mmol/L, using the ADAG formula (eAG = 28.7 × A1C − 46.7).
Often, yes. In the Diabetes Prevention Program, 5–7% weight loss plus ~150 minutes of weekly activity cut progression to diabetes by 58%. Many people move back into the normal range this way.
SteadyRange logs your glucose and weight, shows time in range and estimated A1C as they move, and exports a clean PDF for your next appointment. Private by default.
Try SteadyRange →Medical disclaimer. This page is general education, not medical advice, and uses population-average formulas (ADAG) to estimate average glucose. Individual factors — anemia, pregnancy, kidney disease, hemoglobin variants — can shift real values. Do not start, stop, or change any medication based on this page. Always consult a qualified healthcare provider about your results, targets, and treatment.