For most adults with diabetes, a good A1C is below 7%. That number translates to an estimated average blood sugar of about 154 mg/dL over the previous two to three months. But “good” depends heavily on your age, how long you’ve had diabetes, and what other health conditions you’re managing. Some people do best aiming lower, while others are safer with a higher target.
What A1C Numbers Mean
A1C measures the percentage of your red blood cells that have sugar attached to them. Because red blood cells live for about three months, the test captures your average blood sugar over that window rather than a single snapshot. The diagnostic thresholds are straightforward: below 5.7% is normal, 5.7% to 6.4% is prediabetes, and 6.5% or above indicates diabetes.
Once you have a diabetes diagnosis, the focus shifts from diagnosis to management. An A1C of 7% corresponds to an average blood sugar of roughly 154 mg/dL. At 9%, that average climbs to about 212 mg/dL. Each percentage point matters: the higher your A1C stays over time, the greater your risk of complications affecting your eyes, kidneys, nerves, and heart.
The Standard Target: Below 7%
The American Diabetes Association recommends an A1C below 7% for most non-pregnant adults with diabetes. This target strikes a balance between reducing long-term complications and avoiding the dangers of pushing blood sugar too low. For many people with type 2 diabetes managed through medication, lifestyle changes, or both, getting below 7% is realistic and protective.
That said, the below-7% target is a starting point, not a universal rule. Your doctor may adjust it in either direction based on your individual situation.
When a Stricter Target Makes Sense
Some people benefit from aiming lower than 7%, closer to 6.5%. This is most common in people who are younger, were recently diagnosed, manage their diabetes without medications that cause low blood sugar, and have no significant heart disease. If you can get there without frequent low blood sugar episodes, a tighter target reduces your long-term risk of complications even further.
There’s an important limit, though. Pushing below 6.5% with aggressive medication use can backfire. The American College of Physicians recommends that doctors consider scaling back treatment in patients whose A1C drops below 6.5%, because the risk of dangerous low blood sugar episodes starts to outweigh the benefits. The goal is steady, sustainable control, not the lowest possible number at any cost.
When a Higher Target Is Safer
For many people, aiming for an A1C between 7.5% and 8.5% is actually the safer choice. Several factors can shift your target upward:
- Age and life expectancy. Healthy older adults generally do well with a target below 7.5%. For those with significant health problems or a life expectancy under 10 years, a target of 8% or even 8.5% may be more appropriate.
- Hypoglycemia unawareness. If you’ve lost the ability to feel when your blood sugar drops too low, tighter control becomes dangerous. A higher A1C target gives you a wider safety margin.
- Long duration of diabetes. People who have lived with diabetes for decades often have different needs than those who were recently diagnosed. Years of treatment can make blood sugar harder to predict.
- Multiple chronic conditions. Heart failure, kidney disease, dementia, and other serious illnesses change the risk-benefit calculation. In these cases, avoiding low blood sugar episodes and maintaining quality of life take priority over hitting a specific number.
For people over 80, those living in nursing homes, or those with conditions like end-stage kidney disease or advanced dementia, some guidelines recommend moving away from rigid A1C targets altogether and focusing instead on preventing symptoms and dangerous highs or lows.
Targets for Children and Teens
Children with type 1 diabetes generally aim for an A1C below 7.5%. For children with type 2 diabetes, the target is tighter, below 7%. These goals reflect the fact that younger bodies are still developing and that years of elevated blood sugar compound damage over a lifetime. Tight control in childhood and adolescence pays off significantly in the decades ahead.
Targets During Pregnancy
Pregnancy requires the strictest A1C targets of any situation. Most guidelines recommend an A1C of 6.5% or lower before becoming pregnant if you have preexisting diabetes, to reduce the risk of complications during early fetal development. Once pregnant, the target drops further to below 6%, because even modest elevations in blood sugar can affect fetal growth and increase the chance of birth complications. These tight targets are achievable with close monitoring and frequent adjustments to treatment.
What Affects A1C Accuracy
A1C is reliable for most people, but certain conditions can skew the results. Anything that changes how long your red blood cells survive, such as iron deficiency anemia, sickle cell trait, recent blood loss, or blood transfusions, can make your A1C read artificially high or low. Kidney disease in its later stages can also distort results. If your A1C doesn’t seem to match what your daily blood sugar readings show, that disconnect is worth raising with your doctor, because an alternative test may give a more accurate picture.
How Often to Test
If your blood sugar is well controlled and stable, testing A1C twice a year is typically sufficient. If you’ve recently changed medications, are not meeting your target, or are newly diagnosed, testing every three months gives you and your doctor faster feedback on whether your approach is working. Since the test reflects a rolling average, testing more often than every three months won’t tell you much new.
Putting the Number in Context
A1C is one of the most important numbers in diabetes management, but it doesn’t capture everything. Two people with the same A1C can have very different daily blood sugar patterns. One might have steady numbers all day, while the other swings between high spikes and dangerous lows that average out to the same result. If you use a continuous glucose monitor or check your blood sugar regularly, those patterns matter just as much as the A1C itself. The goal is stable blood sugar within your target range, not just a good number on a quarterly lab test.