Hemoglobin A
Hemoglobin A is the predominant adult hemoglobin form, making up approximately 95-98% of total hemoglobin in healthy adults.
Category: Complete Blood Count
Also known as: hb a
Reference range: 95–98 % (Source: ABIM)
Standard unit: %
High values may indicate
Elevated Hb A relative to abnormal hemoglobin variants is generally favorable.
Low values may indicate
Low Hb A may suggest hemoglobinopathies such as sickle cell disease or thalassemia.
Frequently asked questions
- What is a normal Hemoglobin A level?
- A typical reference range for Hemoglobin A is 95–98 % (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is Hemoglobin A measured in?
- Hemoglobin A 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 Hemoglobin A 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 Hemoglobin A over time?
- Yes. Upload results from any lab and BloodId charts your Hemoglobin A over time against its reference range, so you can see whether the trend is rising, falling, or stable.
Related biomarkers
Source: BloodId admin-reviewed
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