HbA1c

HbA1c (glycated hemoglobin) measures your average blood sugar level over the past 2 to 3 months. It reflects how much glucose has attached to hemoglobin in your red blood cells.

Category: Diabetes & Glycemic

Also known as: hba1c, a1c, hemoglobin a1c, glycated hemoglobin, glycosylated hemoglobin, Hgb A1c, glikozilirani hemoglobin

Reference range: 4–5.6 % (Source: ABIM)

Standard unit: %

High values may indicate

High HbA1c levels may indicate poorly controlled diabetes, prediabetes, or increased risk of diabetic complications such as nerve damage, kidney disease, and cardiovascular disease.

Low values may indicate

Low HbA1c levels are generally normal but may sometimes indicate frequent low blood sugar episodes (hypoglycemia), hemolytic anemia, or blood loss.

Frequently asked questions

What is a normal HbA1c level?
A typical reference range for HbA1c is 4–5.6 % (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
What units is HbA1c measured in?
HbA1c is most commonly reported in %. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
Where do HbA1c reference ranges come from?
BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
Can I track HbA1c over time?
Yes. Upload results from any lab and BloodId charts your HbA1c over time against its reference range, so you can see whether the trend is rising, falling, or stable.

Related biomarkers

Source: MedlinePlus, U.S. National Library of Medicine

How we source our data

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