Normal A1C Range by Age, Gender & Diabetes Status
Normal A1C is below 5.7%. Prediabetes is 5.7%–6.4%. Diabetes is diagnosed at 6.5% or higher. For people managing diabetes, the American Diabetes Association (ADA) recommends an A1C target below 7.0% for most adults — though targets vary by age, health status, and individual circumstances.
A1C Range Reference Table
| A1C % | Category | eAG (mg/dL) | eAG (mmol/L) | Action |
|---|---|---|---|---|
| Below 5.7% | Normal | <117 | <6.5 | Maintain healthy habits |
| 5.7% – 6.4% | Prediabetes | 117–137 | 6.5–7.6 | Lifestyle changes — often reversible |
| 6.5% or higher | Diabetes | ≥140 | ≥7.8 | Confirm diagnosis, begin management |
| Below 7.0% | Target (with diabetes) | <154 | <8.6 | ADA target for most adults |
| Below 8.0% | Target (selected adults) | <183 | <10.2 | Higher target for elderly or complex cases |
Source: ADA Standards of Medical Care in Diabetes 2024 · NIDDK
What Is a Normal A1C?
According to the ADA, a normal A1C for someone without diabetes is below 5.7%. At this level, average blood sugar over the past 2–3 months has been in the healthy range — roughly below 117 mg/dL (6.5 mmol/L).
It's worth noting that A1C values in the lower normal range (e.g., 4.5%–5.2%) are not necessarily "better" — they simply indicate lower average blood sugar, which is typical in people without any glucose regulation issues. For most healthy adults, an A1C between 4.5% and 5.6% is considered solidly normal.
Normal A1C Range by Age
The diagnostic thresholds for prediabetes and diabetes (5.7% and 6.5%) are the same regardless of age. However, treatment targets may differ by age group — older adults often have higher A1C targets to reduce the risk of hypoglycemia.
For a personalized A1C range by age, use our A1C by Age Calculator.
Does Normal A1C Differ by Gender?
The ADA does not set different diagnostic thresholds for men and women — the same cutoffs (5.7% for prediabetes, 6.5% for diabetes) apply to all adults. However, research has identified some nuances worth knowing:
- Women tend to have slightly lower A1C values than men at the same average glucose level — likely due to differences in red blood cell characteristics
- Women with gestational diabetes have specific A1C targets during pregnancy (typically below 6.0%), which differ significantly from standard adult targets
- Hormonal fluctuations during menstrual cycles can cause daily glucose variability, but typically don't affect A1C meaningfully over a 3-month period
- PCOS (polycystic ovary syndrome) is associated with higher insulin resistance, which can elevate A1C — women with PCOS should be screened regularly
Prediabetes A1C Range (5.7%–6.4%)
Prediabetes means blood sugar is higher than normal but not yet high enough to be classified as diabetes. An A1C between 5.7% and 6.4% falls in this range. Importantly, prediabetes is often reversible with lifestyle changes — it does not automatically progress to type 2 diabetes.
According to the NIDDK, the Diabetes Prevention Program (DPP) clinical trial showed that lifestyle interventions — specifically a 5–7% reduction in body weight and 150 minutes of physical activity per week — reduced the risk of progressing from prediabetes to type 2 diabetes by 58% over 3 years.
If your A1C is in the prediabetes range, read our guide: How to Lower Your A1C.
Diabetes A1C Range (6.5% and Above)
An A1C of 6.5% or higher on two separate tests confirms a diagnosis of diabetes, per ADA and WHO guidelines. This corresponds to an eAG of approximately 140 mg/dL (7.8 mmol/L) or higher.
A1C Targets for People Already Managing Diabetes
Once diagnosed, the goal shifts from diagnosis to management. The ADA recommends individualized A1C targets:
- Below 7.0% — the standard target for most non-pregnant adults with type 1 or type 2 diabetes
- Below 6.5% — a tighter target for patients who can achieve it safely without significant hypoglycemia (e.g., early diabetes, young age, long life expectancy)
- 7.0%–8.0% — a more relaxed target for elderly patients, those with hypoglycemia unawareness, limited life expectancy, or multiple chronic conditions
Factors That Affect A1C Results
Several conditions can cause A1C to read falsely high or low, unrelated to actual blood sugar levels:
| Condition | Effect on A1C |
|---|---|
| Iron deficiency anemia | Falsely elevates A1C |
| Vitamin B12 / folate deficiency | May elevate A1C |
| Hemolytic anemia | Falsely lowers A1C |
| Sickle cell trait (HbS) | Can lower or raise depending on assay |
| Chronic kidney disease | May lower A1C |
| Recent blood transfusion | Lowers A1C temporarily |
| Pregnancy (2nd/3rd trimester) | Typically lowers A1C |
If you have any of these conditions, discuss alternative monitoring methods with your doctor — such as fructosamine testing or continuous glucose monitoring (CGM).