Interpret Your Hemoglobin A1c Results
Enter your HbA1c value below and get an instant, free AI interpretation — a plain-English explanation checked against WHO/IFCC reference ranges.
Medical Disclaimer
This AI-generated interpretation is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. Results may vary based on individual health factors not captured here.
Always consult a qualified healthcare professional before making any health decisions. Read full disclaimer →
Hemoglobin A1c Normal Ranges
HbA1c (glycated hemoglobin) measures the percentage of hemoglobin that has glucose permanently attached to it, reflecting average blood glucose over the past 2–3 months.
| Reference Range | Unit | Notes |
|---|---|---|
| 4 – 5.6 | % | Normal (non-diabetic) |
| 5.7 – 6.4 | % | Prediabetes range |
| 6.5 – 99 | % | Diabetes (diagnostic threshold) |
Also reported in: mmol/mol.
Why Doctors Order the Hemoglobin A1c Test
HbA1c predicts the risk of diabetic complications (retinopathy, nephropathy, neuropathy) better than any single glucose measurement. Each 1% reduction in HbA1c reduces the risk of microvascular complications by approximately 35–40% (UKPDS).
How to Enter Your HbA1c Result
Hemoglobin A1c can be reported in % or mmol/mol. Choose the unit printed next to your result on the lab report so it is compared with the matching reference range.
What a Low or High HbA1c Can Be Associated With
Below the reference range
- Hemolytic anemia (shorter RBC lifespan = less glycation — falsely low HbA1c)
- Sickle cell disease and thalassemia
- Recent blood transfusion (donor cells not glycated)
- Excellent diabetes management
- Hypoglycemia risk (treating diabetes too aggressively)
Above the reference range
- Poorly controlled type 2 diabetes
- Type 1 diabetes with inadequate insulin dosing
- Iron deficiency anemia (falsely raises HbA1c)
- Splenectomy (longer RBC lifespan = more glycation)
These are common associations, not a diagnosis. A single result is read alongside your symptoms, history and other tests — discuss it with your doctor.
What Can Change Your HbA1c Result
Before you read too much into a result, consider whether any of these applied:
- Hemolytic anemia (falsely low — RBCs are destroyed before they can accumulate glycation)
- Iron deficiency anemia (falsely high — RBCs live longer, more time for glycation)
- Blood transfusion (dilutes glycated cells, falsely lowering HbA1c)
- Hemoglobin variants (HbS in sickle cell, HbC, HbE) — interfere with some HbA1c assays
Preparing for the test: No fasting required — this is a key advantage of HbA1c over fasting glucose. Can be drawn at any time of day.
Symptoms That Often Prompt HbA1c Testing
- Poorly controlled diabetes symptoms: excessive thirst, frequent urination, blurred vision, fatigue
- Diabetic complications from chronic hyperglycemia: nerve pain, kidney disease, vision loss
Want the full clinical guide to Hemoglobin A1c?
Reference ranges, causes, symptoms, preparation, and FAQs.