Hemoglobin A1c (HbA1c) measured by automated high-performance liquid chromatography (HPLC)
This test measures the average blood sugar levels over the past 2–3 months by checking the percentage of hemoglobin (the oxygen-carrying protein in red blood cells) that is coated with sugar.
["HbA1c reflects long-term blood glucose control and helps assess diabetes management."]
Key facts at a glance
- LOINC
- 50559-4
- Short code
- Hgb Ur Strip.auto-mCnc
- Synonyms
- Hgb Ur Strip.auto-mCnc
- Category
- hematology
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- test-strip-automated
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why is this test important?
HbA1c is a key marker for managing diabetes and prediabetes. It provides insight into how well your blood sugar has been controlled over time, helping doctors adjust treatment plans if needed.
How is this test performed?
A small blood sample is taken from your arm and processed using automated HPLC to measure the percentage of hemoglobin bound to glucose. This method is precise and avoids daily blood sugar fluctuations.
What does a result mean?
Results are typically reported as a percentage (e.g., 5.7%–6.4% may indicate prediabetes, while 6.5% or higher suggests diabetes). Your doctor will interpret results in the context of your overall health.
Common reasons for testing
HbA1c is often ordered during diabetes screening, routine check-ups, or when managing chronic conditions like heart disease or kidney problems. It’s also used to monitor treatment effectiveness in people with diabetes.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: HbA1c is critical for diagnosing diabetes (typically ≥6.5%) and guiding treatment. Lower-than-normal levels may indicate poor glucose control in people with diabetes, while higher levels may signal undiagnosed diabetes or poor management.
Short name
HbA1c
Frequently asked questions
What does an HbA1c test tell me about my diabetes?
How often should I get an HbA1c test?
Can lifestyle changes affect my HbA1c results?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy