What is HbA1c and how is it used to measure diabetes?⁠4,26

A HbA1c or A1c test is used by doctors and healthcare professionals to measure your average blood sugar level over the last 2-3 months. The test result is used to diagnose, monitor, and manage treatment decisions for diabetes.

HbA1c is measured as a percentage (%).

Why is HbA1c important?4

In general, a higher HbA1c indicates a higher risk of long-term diabetes complications. If you have either type 1 or type 2 diabetes, your doctor will check your HbA1c levels to decide on the best treatment plan for you, and help you set a target to lower your HbA1c.

What is considered a normal HbA1c range?⁠3


A healthy HbA1c is below 5.7%


HbA1c between 5.7-6.4% indicates prediabetes. This means you are at risk of developing diabetes


HbA1c of 6.5% or above indicates diabetes

Gestational diabetes

If you do not have diabetes, HbA1c of 5.9% in the first 15 weeks of pregnancy may mean you are at higher risk for gestational diabetes.

HbA1c on its own does not tell the full story

HbA1c does not give a full picture of your blood sugar levels. It does not account for the ups and downs of your blood sugar within a day or show patterns in your blood sugar over time. HbA1c also can't tell you whether you experience hypoglycemia. Gaining insight into what's affecting your blood sugar can help customize a diabetes management plan suited to your individual needs and routine.

Time in Range (TIR) is increasingly being used to assess blood sugar in combination with HbA1c. TIR is a measurement of how much of the day your blood sugar spends within your target range. It is measured as a percentage (%).3 The higher the TIR, the better the glucose control.

People can have similar HbA1c but different TIR⁠4

People can have similar HbA1c but different TIR

Every 10% increase in TIR can lower HbA1c by 0.5-0.8%⁠24

What is recommended Time In Range (TIR) if I have diabetes?⁠4

Type 1 & type 2

At least 70% of the day: 3.9 - 10 mmol/L

Older or high-risk type 1 & type 2

At least 50% of the day: 3.9 - 10 mmol/L

Type 1 during pregnancy

At least 70% of the day: 3.5 - 7.8 mmol/L

FreeStyle Libre can help you increase your Time in Range (TIR) and reduce HbA1c⁠11,27


FreeStyle libre can show you the Time In Target you had in the last 7/14/30/90 days.

Type 1 or type 2

Patients who scanned more frequently had 43% higher TIR*11


Type 1

HbA1c reduced by 0.53% on average, after 12-16 weeks using FreeStyle Libre†27

Type 2

HbA1c reduced by 1.1% on average, after 22 weeks using FreeStyle Libre^27

*Comparing 2 groups from lowest to highest scan rate (3.6 and 39.5 scans/day), p=0.001.
p<0.0001 vs. baseline
^in people using basal insulin, p<0.001 vs. baseline

References: 3. American Diabetes Association. Diabetes Care. 2020;43(1):S77–S88. 4. Battelino T, et al. Diabetes Care. 2019;42(8):1593–1603. 11. Evans M, et al Diabetes Ther. 2020;11(1):83–95. 24. Vigersky RA, et al. Diabetes Technol Ther. 2019;21(2):8–-85. 26. Wagner J, et al. Diabetes Technol Ther. 2005:7(4):612–9. 27. Wright E, et al. Diabetes Spectrum. 2021;34(2):184–189.

Disclaimers - 1. Images are for illustration purpose only. No actual patient data. Any person depicted in the photos is a model. Children shall not use without supervision. 2. The information mentioned in this document is only suggestive for patient education and shall not be considered as a substitute for doctor's advice or recommendations from Abbott. Please consult your doctor for more information.