Key Takeaways
- Monitor your average blood sugar over a three-month period via an A1c test.
- The results shown on an A1c chart indicate normal blood sugar under 5.7%; higher numbers indicate prediabetes or diabetes.
The A1c chart shows your blood sugar levels, indicating whether they are normal, prediabetic, or diabetic. The A1c test measures your average blood glucose over a three-month period.
What an A1c Chart Tells You
The A1c test, also called the hemoglobin A1c or HbA1c, measures how much sugar attaches to hemoglobin, a type of red blood cell, as it enters your bloodstream. Everyone has glucose coating their hemoglobin, but people with high blood glucose levels have more.
When your healthcare provider checks your A1c, they measure how much glucose coats your hemoglobin. They use these measurements to estimate your three-month average blood glucose.
A1c levels are sorted into ranges on a chart, categorized as normal, prediabetic, or diabetic.
Illustration by Tara Anand for Verywell Health
These are general guidelines, but your target range may vary based on factors like age and health status.
If you have diabetes, your goal may be over 7% in the following situations:
- Severe hypoglycemia (low blood sugar)
- Chronic kidney disease
- Nerve problems
- Cardiovascular disease
- Difficulty managing blood sugar
- Limited life expectancy
Estimated Average Clucose (eAG)
While A1c is shown as a percentage, you can convert it into the same units (mg/dL or mmol/L) as your regular blood sugar readings. This is called estimated average glucose (eAG).
The formula to convert to eAG is 28.7 X A1C – 46.7 = eAG.
Steps to Reach Your Target A1c Range
Your A1c goal depends on factors like age, diagnosis, and other medical conditions. For many with diabetes, an A1c under 7% is healthy, but your personal goal can vary.
To help reach your goal, consider:
- Checking your blood glucose levels regularly
- Developing and following a healthy eating plan
- Getting enough sleep
- Getting regular exercise
- Reaching a healthy weight and maintaining it
- Reducing stress
- Taking your diabetes and other medications as prescribed
High A1c Without Diabetes
Beyond diabetes, various factors can affect your A1c:
- Anemia
- Blood transfusions
- Certain blood disorders
- Heavy bleeding or blood loss
- Kidney disease
- Liver failure
- Pregnancy
- Recreational drug use
- Some medications
If you have any of these conditions and your A1c is out of range, your healthcare provider may ask for additional testing or repeat your A1c later.
Benefits of Knowing Your A1c Range
Healthcare providers use the A1c test to glean information about how your metabolism and typical diet affect your blood sugar:
- If your A1c range indicates “prediabetes” (5.7% to 6.5%), you are at risk of developing type 2 diabetes.
- An A1c level of 6.5% or higher may result in an official diagnosis of type 2 diabetes, leading your provider to create a treatment plan to control your blood sugar.
- If you get a high daily glucose reading, but your A1c falls within the normal range of 5.7% or less, the spike is likely related to your last meal and not an ongoing issue with your blood sugar levels.
People who have already been diagnosed with diabetes usually have their A1c levels checked every six months.
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