Before going into the details of the A1C conversion chart, let's review some basics about A1C.
What is an A1C? The A1C, also known as HbA1c or glycated hemoglobin, is a blood test that helps you assess how well your diabetes management plan is working.
What do the A1C numbers mean? The A1C test tells you your average blood sugar level over the past 2 to 3 months. The newest blood sugar has more influence on the a1c number than the oldest blood sugar numbers.
How is hemoglobin A1c Measured? A1c is measured by separating Hba1c based on its charge and size from the other hemoglobin. Hba1c is a component in blood separated by high-pressure (or performance) liquid chromatography (HPLC).
What is an excellent a1c level? The average A1c value for those not diagnosed with diabetes (healthy non-diabetics) is 4.2 to 4.6% for more visit Healthy A1C goal.
How often should I take an A1C test? Your doctor usually insists on 2 to 4 times a year.
How accurate is the A1C test? The A1C is now standardized, and the acceptable variance can be within 0.5%. So, if your result is 6.5%, the actual reading could be anywhere from 6 to 7% (i.e., 6.5 - 0.5 to 6.5 + 0.5). Some health conditions could affect the accuracy of the A1c. Visit 9 undesirable factors affecting the Hba1c test for more details.
What is eAG? eAG is estimated average glucose, a newer term you may see reported by your doctor. The a1c chart in this article provides corresponding eAG (blood glucose in mg/dl or mmol/L) value that you can easily relate with your daily blood sugar measuring unit.
How do eAG and the average reading on the glucose monitor differ? Because people with diabetes monitor their blood glucose frequently during hypoglycemic episodes, their average meter readings are usually lower than their estimated average glucose (eAG). As a result, the average meter reading is probably lower than eAG.
A glucose monitor measures your blood glucose at that instant, whereas eAG or A1C represents an average of your glucose levels 24/7 for the last three months. It might include times when people with diabetes are less likely to check their blood glucose.
Can the A1C test diagnose both prediabetes and diabetes? Nowadays, doctors use the A1C test for diabetes screening due to its non-fasting requirement. A1c should be complemented by other tests for an accurate diabetes diagnosis.
What are the benefits of the A1C test? Research has demonstrated the crucial role of the A1C test in preventing complications associated with diabetes. Major research studies, including DCCT, UKPDS, EDIC, and EPIC-Norfolk, established the connection between A1C levels and diabetic complications. Visit Benefits of A1C in Diabetes Control for more information.
What are the limitations of the hemoglobin A1c test? Certain medical conditions may falsely increase or decrease the Hba1c number. For more detail visit A1C test errors.
How can I lower my a1c number? Achieving your set target is not easy, but achievable. It requires patience, the wish to learn, the ability to analyze, the willpower to accept failures, and stick with lifestyle changes. Visit How to lower A1C? to learn more.
Does aging affect A1C level? In the FOS and NHANES cohorts, A1C levels are positively associated with age in nondiabetics. Linear regression revealed 0.010 to 0.014 unit increases in A1C per year in the nondiabetics. A1C was 6.0% to 5.6% for nondiabetic individuals aged below 40 years and 6.6% to 6.2% for individuals aged 70 years.
Why do you need an A1C level chart?
A1C test in % is confusing, because we used to measure glucose levels in mg/dl or mmol/l. The A1C chart helps convert this A1C in % to its equivalent established average blood glucose (eAG), which is easier to interpret.
3 formulas from clinical studies to convert A1C to eAG
- Diabetes Control and Complications Trial (DCCT) study.
- A1c-Derived Average Glucose (ADAG) Study.
- Translating HbA1c measurements into estimated average glucose values in pregnant women with diabetes. Diabetologia Volume 60, pages 618–624, (2017).
A1C Calculator based on DCCT Formula
Instead of reading the chart enter a1c level to know the equivalent blood glucose level using the a1c calculator below. This calculator is based on the DCCT study and the formula they provided.
DCCT based A1C Chart
Diabetes Control and Complications Trial (DCCT) study of 1400 patients with Type 1 diabetes performed 24-hour, 7-point capillary blood glucose profiles (three pre-meal tests, three post-meal (after 90 minutes) tests, and one at bedtime) in the home. And correlate it with quarterly A1C.
The established Average Glucose eAG in mg/dL = (35.6 x HbA1c) - 77.3. or
The established Average Glucose eAG in mmol/l = (1.98 x HbA1c) – 4.29.
Reference: Diabetes Care 25:275-278, 2002. Diabetes Control and Complications Trial (DCCT), New England Journal of Medicine 1993; 329:977-986.
DCCT A1C conversion formula seems to work best for people with type 1 diabetes, because this formula is derived from type 1 diabetes.
Dr. Richard K. Bernstein, is the author of the popular book "Diabetes Solution" and he recommends DCCT's A1C formula to establish average glucose eAG. Additionally, it might be suitable for people with type 1 diabetes, because the study included only type 1 diabetes patients.
Printable A1C chart pdf
A handy DCCT A1C chart is always useful for ready reference. So have your copy of this printable a1c chart and a1c chart in pdf format.
ADAG-based A1C Calculator
Instead of reading the chart you can just enter your a1c level to know the equivalent blood glucose level using this Hba1c calculator below. This calculator is based on the ADAG study and the formula derived.
ADAG-based HbA1c Chart
The HbA1C chart/table provides hba1c in % to eAG in mg/dl or mmol/l using the ADAG formula.
The A1c-derived Average Glucose (ADAG) Study is constituted to define the mathematical relationship between HbA1c and eAG. This study included 507 subjects 268 T1D, 159 T2D, and 80 non-diabetics from 10 international centers. Patients were between 18-70 years, and diabetics had stable control. eAG calculation is based on the results from at least two days of continuous glucose monitoring performed four times, with 7-point daily self-monitoring of capillary glucose carried out at least three days per week. Reference: Translating the A1C Assay Into Estimated Average Glucose Values, Diabetes Care 31:1473-1478, 2008.
The establishes Average Glucose eAG in mg/dl = (28.7* hba1c)-46.7 or
The establishes Average Glucose eAG in mmol/l = (1.59 x HbA1c)-2.59
Printable hba1c chart pdf & png
A handy chart is always useful for ready reference. Print your copy with this printable hba1c chart and hba1c chart in pdf format.
A1C Calculator for Pregnant women with diabetes
HbA1c is considered unreliable for assessing glucose control during pregnancy owing to physiological changes that may be attributed to increased red cell production, shortened red cell life span, reduced red cell affinity for glucose, iron deficiency, and iron supplementation.
A clinical study came up with a formula for pregnant women with diabetes. Reference: Translating HbA1c into eAG values in pregnant women with diabetes, Diabetologia Volume 60, pages 618–624, (2017). This formula is for those during pregnancy. Pregnancy-specific estimated average glucose:
PeAG in mmol/l = 6.78 + [0.43 x (A1c - 6.3)] + [0.04 x (Gestation week - 21)] - [0.001 x (Gestation week^2 - 528)].
Caution: Many pregnant women suffer from iron deficiency in the third trimester. Studies have shown that iron deficiency increases HbA1c levels. According to these results, the Japanese Society of Diabetes and Pregnancy recommends checking glycated albumin (GA) to help prevent perinatal complications in mothers, fetuses, and neonates.
Is your A1C high? Don’t panic!
If your A1C number is higher, say over 7 or 8%, do not worry! You can lower your A1C with healthy lifestyle changes. First, you should decide your A1C target number and should know the health benefits of A1C. Then automatically you will become interested in achieving your target and finally learn how to lower A1C.
Many people ask, what does it mean if I have a high hba1c and normal blood sugars? Many others may also ask, what does it mean if I have good hba1c and elevated fasting glucose? If you are one among them, visit the hbA1C glucose level relationship.