Hemoglobin A1c (HbA1c) with Mass Fraction Measurement
This test measures the percentage of hemoglobin that is coated with sugar (glycated hemoglobin), reflecting your average blood sugar levels over the past 2–3 months.
["HbA1c helps track long-term diabetes control and glucose management."]
Key facts at a glance
- LOINC
- 54073-2
- Short code
- Hgb C MFr DBS
- Synonyms
- Hgb C MFr DBS
- Category
- hematology
- Sample
- serum
- Container
- Red-top tube (SST)
- 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
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What HbA1c Test Measures
HbA1c measures the proportion of hemoglobin molecules that have sugar (glucose) attached. This attachment happens when blood sugar levels are consistently high over time. The test provides a snapshot of your average blood sugar levels during the red blood cell’s lifespan (typically 2–3 months).
Why This Test Matters
HbA1c is crucial for diagnosing diabetes and managing blood sugar levels. It helps doctors assess whether your treatment plan is effective and adjusts it as needed to prevent complications like nerve damage, kidney disease, or heart problems.
How the Test Works
Blood is drawn, and the hemoglobin is separated from other blood components. The test then measures the fraction of hemoglobin that has sugar attached, using specialized laboratory techniques to quantify this glycation.
Common Uses
Doctors use HbA1c to diagnose type 1 and type 2 diabetes, monitor pre-diabetes, and evaluate long-term diabetes management. It’s also useful for assessing how well diabetes medications or lifestyle changes are working.
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
Short name
HbA1c
Frequently asked questions
HbA1c is a reliable indicator of blood sugar control because it reflects long-term glucose exposure. While individual results can vary slightly, consistent trends help guide treatment decisions and reduce the risk of diabetes-related complications.
How often should I get this test?
What factors can 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