A good A1C reading for someone without diabetes is below 5.7%. That number means your average blood sugar over the past two to three months has been in a healthy range. If you already have diabetes, the target shifts: most adults aim for below 7%, which translates to an estimated average blood sugar of about 154 mg/dL. Where you fall on this spectrum, and what number you should personally aim for, depends on your age, health status, and whether you’re managing an existing diagnosis.
What the A1C Ranges Mean
The A1C test 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 a rolling average of your blood sugar rather than a single snapshot. Three clear categories define the results:
- Normal: Below 5.7%
- Prediabetes: 5.7% to 6.4%
- Diabetes: 6.5% or higher
A result in the prediabetes range is a signal that your body is starting to lose its ability to process sugar efficiently. It doesn’t mean diabetes is inevitable. Losing a modest amount of weight and increasing physical activity can often bring that number back down. A result at or above 6.5% on two separate tests is typically enough to confirm a diabetes diagnosis.
Targets if You Have Diabetes
Once you’re managing diabetes, “good” becomes a more personalized number. The general recommendation for most non-pregnant adults is an A1C below 7%. Studies have consistently shown that staying under this threshold significantly reduces the risk of complications affecting the eyes, kidneys, and nerves, especially when tight control starts early in the course of the disease.
Some people can safely aim lower. If you can keep your A1C below 7% without experiencing episodes of dangerously low blood sugar (hypoglycemia), your doctor may encourage you to push toward 6.5% or even lower. The key word is “safely.” Aggressive blood sugar lowering that causes frequent crashes can be just as harmful as running high.
On the other end, a more relaxed target of below 8% is sometimes more appropriate. This applies to people who have other serious health conditions, a history of severe low blood sugar episodes, or a limited life expectancy where the long-term benefits of tight control are less relevant. The goal is always to balance blood sugar management against the real risks of overtreatment.
Targets for Children and Adolescents
For most children and teens with type 1 diabetes, the recommended A1C target is also below 7%. However, as automated insulin delivery systems have improved, guidelines now encourage pushing toward below 6.5% for kids who can reach that level without significant low blood sugar episodes, excessive weight gain, or added stress on the child and family.
Children and adolescents with type 2 diabetes generally have a target of below 6.5% from the start. The rationale is straightforward: type 2 diabetes in young people tends to progress faster and carry a higher risk of complications than type 1, while the risk of dangerous lows is typically lower since most aren’t on insulin.
Targets During Pregnancy
Pregnancy calls for tighter control. For women with pre-existing diabetes who are pregnant or planning to become pregnant, the recommended A1C is between 6% and 6.5%. As pregnancy progresses into the second and third trimesters, getting below 6% is ideal if it can be done without causing low blood sugar. An A1C at or above 6.5% during pregnancy is linked to higher rates of complications, including having an unusually large baby. Before conception, keeping A1C below 6.5% helps reduce the risk of birth defects.
Targets for Older Adults
Guidelines for older adults reflect the reality that health in your 70s and 80s varies enormously from person to person. A healthy, independent older adult with few other medical issues can generally aim for the standard target of below 7%. But for someone managing multiple chronic conditions, cognitive decline, or significant functional limitations, most guidelines recommend a target of below 8%, and some go as high as 8.5%.
The reasoning is practical. Tight blood sugar control requires careful medication management, and the consequences of a severe low blood sugar episode (falls, confusion, hospitalization) become more dangerous with age. For someone with a life expectancy under five years, preventing complications that take a decade to develop matters less than avoiding the immediate dangers of hypoglycemia.
When A1C Results Can Be Misleading
The A1C test is reliable for most people, but certain conditions can throw off the results. Because the test depends on red blood cells, anything that changes how long those cells survive or how they behave will skew the number.
Iron deficiency anemia is one of the most common culprits. It artificially inflates A1C, making blood sugar control look worse than it actually is. This is especially relevant in pregnancy, where iron deficiency is common and can push A1C readings higher in the later months even when blood sugar is normal. Once the iron deficiency is treated, A1C drops back to a more accurate level.
Conditions that destroy red blood cells faster than normal, like hemolytic anemia or recovery from significant blood loss, have the opposite effect. They falsely lower A1C because the red blood cells haven’t been around long enough to accumulate sugar. Sickle cell trait and other hemoglobin variants can also interfere with the accuracy of certain testing methods. Kidney failure complicates things further, as chemical changes to hemoglobin in dialysis patients tend to make A1C an unreliable marker. In all of these situations, direct blood sugar monitoring gives a more accurate picture.
How Often to Get Tested
If you have prediabetes, once a year is the typical recommendation. For people with diabetes whose blood sugar is stable and within their target range, twice a year is usually sufficient. You’ll need more frequent testing if you use insulin, if your treatment plan has recently changed, or if you’re struggling to stay within your target. Your results over time matter more than any single reading, so consistent testing on a regular schedule gives you and your doctor the clearest view of your trajectory.