A good A1c for most adults with type 2 diabetes is below 7%, which translates to an estimated average blood sugar of about 154 mg/dL. That’s the target the American Diabetes Association recommends in its 2025 standards of care. But “good” isn’t one number for everyone. Your ideal target depends on your age, how long you’ve had diabetes, and whether aggressive blood sugar control creates other risks for you.
What A1c Numbers Actually Mean
The A1c test measures the percentage of your red blood cells that have glucose attached to them, giving you a picture of your average blood sugar over the past two to three months. It’s more useful than a single finger-stick reading because it captures the bigger trend rather than a snapshot of one moment.
The CDC uses these ranges for diagnosis:
- Normal: below 5.7%
- Prediabetes: 5.7% to 6.4%
- Diabetes: 6.5% or above
If you already have a type 2 diabetes diagnosis, those diagnostic cutoffs aren’t your management targets. Your goal is to bring your A1c down into a range that protects you from complications without pushing your blood sugar dangerously low.
You can roughly convert any A1c into an estimated average glucose using this formula: multiply your A1c by 28.7, then subtract 46.7. So an A1c of 7% works out to about 154 mg/dL as a daily average, and an A1c of 8% corresponds to roughly 183 mg/dL.
The Standard Target: Below 7%
For most nonpregnant adults who aren’t experiencing frequent low blood sugar episodes, an A1c below 7% is the widely accepted goal. This target is backed by large studies showing meaningful protection against the complications that make diabetes dangerous over time. Data from the landmark UK Prospective Diabetes Study found that someone maintaining a 7% average A1c had a 37% lower risk of microvascular complications (damage to small blood vessels in the eyes and kidneys) compared to someone averaging 8%. The overall risk of any diabetes-related health problem dropped by 21%.
Those aren’t small numbers. The difference between 7% and 8% might sound minor, but over years it significantly changes your odds of developing vision loss, kidney disease, and nerve damage.
When a Tighter Target Makes Sense
The American Association of Clinical Endocrinologists sets an even more ambitious goal: an A1c of 6.5% or lower for people who don’t have serious concurrent health problems and who are at low risk of hypoglycemia (blood sugar dropping too low). This tighter target is most realistic if you were diagnosed relatively recently, respond well to treatment, and can manage your blood sugar without medications that carry a high risk of lows.
Younger adults with decades of life ahead often benefit from aiming closer to 6.5%, since the protective effects of tighter control compound over time. If you’re early in your diabetes journey and your body still produces some insulin, reaching this range may be achievable with lifestyle changes and a single medication.
When a Higher Target Is Safer
Not everyone should chase the lowest possible A1c. Pushing blood sugar too low can cause hypoglycemia, which ranges from uncomfortable shakiness and confusion to seizures and loss of consciousness in severe cases. For some people, the risks of aggressive treatment outweigh the benefits of a lower number.
A less stringent goal of 7% to 8% is generally more appropriate if you:
- Have a long history of diabetes spanning many years, especially if reaching lower targets has been consistently difficult
- Have experienced severe hypoglycemia or have trouble recognizing when your blood sugar is dropping (called hypoglycemia unawareness)
- Are older or have other serious health conditions like advanced kidney disease, heart disease, or frailty
- Have a limited life expectancy, where the long-term benefits of tight control won’t have time to materialize
The ADA puts it plainly: a target below 8% may be appropriate when the harms of treatment are greater than the benefits. For a healthy older adult, there’s no automatic reason to loosen the goal just because of age. But when someone is managing multiple serious conditions, the priority shifts from optimizing a number to avoiding dangerous lows and maintaining quality of life.
Why Every Percentage Point Matters
If your A1c is currently 9% or 10%, getting it down to 8% delivers real health benefits, even though 8% is above the standard target. The relationship between A1c and complications isn’t all-or-nothing. Each point you lower it reduces the strain on your blood vessels, kidneys, and nerves. Progress toward any lower number counts, even if you don’t reach the textbook goal right away.
That said, the benefits of going lower do have a ceiling. Dropping from 7% to 6% doesn’t produce the same dramatic risk reduction as dropping from 9% to 8%. And for people using insulin or certain other medications, the lower you push, the more carefully you need to watch for hypoglycemia. The goal is finding the lowest A1c you can maintain safely and sustainably.
How Often to Test Your A1c
If your A1c is stable and within your target range, testing every six months is sufficient. If you’re not at your goal, or you’ve recently changed your treatment plan, testing every three months gives you and your doctor timely feedback on whether adjustments are working. Clinical guidelines recommend against testing more than four times per year, since the test reflects a two-to-three-month average and more frequent checks won’t reveal useful new information.
Keep in mind that certain conditions can skew A1c results. Iron deficiency anemia, kidney disease, and some blood disorders can make the number read higher or lower than your actual average blood sugar. If your A1c doesn’t match what your daily glucose readings suggest, your doctor may use alternative monitoring methods like fructosamine testing or continuous glucose monitoring to get a clearer picture.
Putting Your Number in Context
A “good” A1c is ultimately the one that balances protection from complications with safety from low blood sugar, fits your life circumstances, and is achievable without treatment that makes you miserable. For most people with type 2 diabetes, that means below 7%. For some, it’s 6.5%. For others, staying under 8% is the right call. The number on your lab report matters less than the trajectory: if you’re moving in the right direction and staying there, you’re doing the most important thing for your long-term health.