A good A1C level for someone without diabetes is below 5.7%, which translates to an estimated average blood sugar of about 97 to 126 mg/dL over the previous two to three months. If you have diabetes, the target shifts: most adults should aim for an A1C below 7%, though your ideal number depends on your age, overall health, and treatment plan.
What the A1C Ranges Mean
The A1C test measures the percentage of your red blood cells that have glucose attached to them. Because red blood cells live for roughly three months, the test captures a rolling average of your blood sugar rather than a single snapshot. Three categories define where you stand:
- Normal: below 5.7%
- Prediabetes: 5.7% to 6.4%
- Diabetes: 6.5% or above
A diagnosis based on A1C requires confirmation with a second test unless you already have obvious symptoms of diabetes, like excessive thirst, frequent urination, or unexplained weight loss. A single result at 6.5% doesn’t automatically mean you have diabetes; it means you need a follow-up to confirm.
How A1C Translates to Daily Blood Sugar
A1C percentages can feel abstract. Converting them to estimated average glucose (eAG) makes the number more intuitive, especially if you also check your blood sugar with a finger stick or continuous monitor.
- A1C 5%: ~97 mg/dL
- A1C 6%: ~126 mg/dL
- A1C 7%: ~154 mg/dL
- A1C 8%: ~183 mg/dL
- A1C 9%: ~212 mg/dL
- A1C 10%: ~240 mg/dL
These are averages, so an A1C of 7% doesn’t mean your blood sugar sits at 154 mg/dL all day. It could mean mostly normal readings with frequent spikes, or moderately elevated readings around the clock. That’s why many clinicians look at A1C alongside daily glucose patterns to get the full picture.
Targets for People With Diabetes
The American Diabetes Association recommends an A1C below 7% for most adults with diabetes. That target balances meaningful protection against complications with a manageable risk of blood sugar dropping too low. For many people, getting below 7% is a realistic and worthwhile goal.
Your personal target may be different. Older adults, people with a history of severe low blood sugar episodes, or those managing other serious health conditions may be better served by a slightly higher target, sometimes in the range of 7.5% to 8%. On the other hand, younger, otherwise healthy adults who can maintain tighter control without frequent lows may benefit from pushing closer to 6.5%. The right number is one you can sustain safely.
For children and adolescents with type 1 diabetes, international guidelines now recommend an A1C of 6.5% or below when advanced technology like continuous glucose monitors and automated insulin pumps are available. Without those tools, the target is 7% or below, the same as for most adults.
Why Each Percentage Point Matters
The relationship between A1C and complications is not binary. You don’t cross a line and suddenly face problems. Instead, risk climbs steadily with each percentage point. Data from a large population study of over 600,000 adults found that each 1% increase in A1C was associated with an 18% increase in the risk of heart attack, even after accounting for other risk factors.
The same gradient applies to damage to small blood vessels, which affects your eyes, kidneys, and nerves. Dropping your A1C from 9% to 8% carries real protective value, even if 8% is still above the standard target. Progress matters more than perfection, and any sustained reduction lowers your long-term risk.
Lowering Your A1C Through Lifestyle
Exercise is one of the most reliable ways to bring down A1C, and the dose matters. A study published in the American Journal of Managed Care found a clear dose-response relationship: for every additional two exercise sessions per month, A1C dropped by about 0.15%. That effect was strongest for aerobic exercise (walking, cycling, swimming) and combined aerobic-plus-resistance training. Resistance training alone didn’t produce a statistically significant reduction in A1C.
The people who benefited most from increasing exercise were those under 55, men, and those starting with an A1C of 7.5% or higher. If your A1C is already close to target, the incremental benefit of more exercise is smaller, though the cardiovascular and metabolic advantages continue well beyond glucose control.
Diet plays an equally important role, though it’s harder to isolate a single number. Reducing refined carbohydrates and added sugars, increasing fiber intake, and managing portion sizes all contribute to lower post-meal blood sugar spikes, which directly influence A1C over time. Most people see the largest improvements when they combine dietary changes with consistent physical activity rather than relying on one alone.
When A1C Results Can Be Misleading
The A1C test is reliable for most people, but certain conditions can skew results in either direction. According to the CDC, factors that may falsely raise or lower your A1C include:
- Severe anemia
- Kidney failure or liver disease
- Blood disorders like sickle cell anemia or thalassemia
- Recent blood loss or blood transfusions
- Certain medications, including opioids and some HIV treatments
- Early or late pregnancy
If any of these apply to you, your A1C might not accurately reflect your true average blood sugar. In those cases, your doctor may rely more heavily on direct glucose measurements, such as a fasting blood sugar test or a glucose tolerance test, to get an accurate assessment.
How Often to Get Tested
If you don’t have diabetes and your results are normal, testing every three years is generally sufficient unless you have risk factors like obesity, a family history of diabetes, or a previous prediabetes result. For people with prediabetes, annual testing helps track whether lifestyle changes are keeping things stable or whether you’re trending toward diabetes.
If you have diabetes and your blood sugar is well controlled on a stable treatment plan, testing twice a year is typical. When your treatment changes or you’re not meeting your target, testing every three months gives you and your care team faster feedback on whether adjustments are working. Since the test reflects a two-to-three-month average, testing more frequently than every 12 weeks won’t give you meaningfully new information.