A normal A1C is below 5.7%, and most adults with diabetes should aim for an A1C under 7%. But the “right” number depends on your age, health status, and whether you’re managing an existing diagnosis or trying to stay in a healthy range. Here’s what the numbers mean and where yours should fall.
The Three A1C Ranges
The A1C test measures your average blood sugar over the past two to three months. It’s reported as a percentage, and there are three clear categories:
- Normal: below 5.7%
- Prediabetes: 5.7% to 6.4%
- Diabetes: 6.5% or higher
If your result comes back at 5.7% or above, that doesn’t necessarily mean you have diabetes, but it does mean your blood sugar has been running higher than ideal. The prediabetes range is a warning zone where lifestyle changes can still reverse the trend before it progresses.
What Your A1C Translates to in Daily Blood Sugar
A1C percentages can feel abstract. It helps to know what they look like as an average daily blood sugar reading. Each percentage point corresponds to roughly 29 mg/dL of average glucose:
- A1C of 6%: average blood sugar of about 126 mg/dL
- A1C of 7%: about 154 mg/dL
- A1C of 8%: about 183 mg/dL
- A1C of 9%: about 212 mg/dL
These are averages, so your actual blood sugar swings higher and lower throughout the day. But this conversion gives you a concrete sense of what your A1C reflects in terms your glucose meter would show.
The Standard Target if You Have Diabetes
The American Diabetes Association recommends an A1C below 7% for most non-pregnant adults with diabetes. This target is grounded in large clinical trials showing that keeping A1C around 7% reduces the risk of complications affecting the eyes, kidneys, and nerves by 50 to 76% compared to running at 9% or higher.
Pushing A1C even lower, from 7% down to 6%, does offer additional protection against these small-vessel complications. But the extra benefit shrinks with each fraction of a percent, while the risk of dangerous blood sugar lows increases. For people who have had diabetes for many years or who are at significant risk of heart disease, trying to reach near-normal levels can actually cause more harm than good. That’s why the general target stays at “under 7%” rather than “as low as possible.”
When a Higher Target Makes Sense
Not everyone should chase the under-7% goal. Your ideal A1C depends on several personal factors, and for some people a higher number is actually safer.
Older adults with multiple chronic conditions generally do better with a target of 8% or below. The priority shifts from tight blood sugar control to avoiding episodes where blood sugar drops too low, which can cause falls, confusion, and hospitalization. For people in poor overall health, or those with significant cognitive or functional limitations, the goal may be relaxed even further to around 8.5%, which translates to an average blood sugar of about 200 mg/dL. The focus at that point is quality of life and avoiding dangerous extremes in either direction.
Other situations that call for a less aggressive target include a history of severe low blood sugar episodes, reduced awareness of low blood sugar symptoms, and advanced kidney disease. The common thread is that the risk of hypoglycemia outweighs the long-term benefit of tighter control.
Tighter Targets During Pregnancy
Pregnancy flips the equation. Because high blood sugar during early development raises the risk of birth defects and complications, the targets are stricter than at any other time. Before conception, the goal is an A1C below 6.5%. During pregnancy itself, the recommended range is 6 to 6.5%, and an A1C below 6% is considered optimal as long as it can be achieved safely.
In the second and third trimesters, keeping A1C below 6% is associated with the lowest risk of having an unusually large baby, while levels at or above 6.5% start to increase the chance of other complications. A1C is considered a secondary tool during pregnancy, though. Frequent daily blood sugar checks give a more real-time picture since blood sugar targets need to be managed much more tightly week to week.
How Lifestyle Changes Move the Number
If you’re in the prediabetes range or working to lower a diabetes-level A1C, lifestyle changes can make a meaningful difference. A real-world program that combined diet changes, exercise, and weight loss over 12 weeks tracked the results across nearly 600 people with diabetes. Those who started with an A1C of 9% or higher saw an average drop of 2.5 percentage points. People starting between 8% and 9% dropped about 1.2 points, and those already below 8% still improved by about half a point.
The pattern makes sense: the higher your starting point, the more room there is to improve. But even a half-point drop matters. Moving from 7.5% to 7% crosses the threshold into the recommended range and meaningfully lowers your risk of complications over time.
How Often to Get Tested
Because A1C reflects the lifespan of your red blood cells, which turn over every 90 to 120 days, testing more often than every three months won’t give you useful new information. If you recently changed your diet, started exercising, or adjusted your treatment, it takes at least three months for the old blood cells to cycle out and the new average to show up in your results.
If your A1C has been stable and consistently at your target, testing every six months is reasonable. If you’re actively trying to bring it down or have recently made changes, every three months gives you a clear picture of whether those changes are working.