Hemoglobin A1c (HbA1c) measured by high-performance liquid chromatography (HPLC)
This test measures the percentage of hemoglobin that is coated with sugar, reflecting your average blood sugar levels over the past 2–3 months.
["HbA1c helps doctors track diabetes control and long-term blood sugar health."]
Key facts at a glance
- LOINC
- 77062-8
- Short code
- HPD Fam Mut Anl Bld/T
- Synonyms
- HPD Fam Mut Anl Bld/T
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What HbA1c Tests Measure
HbA1c reflects the amount of glucose (sugar) that has attached to hemoglobin, the protein in red blood cells that carries oxygen. This attachment is a stable marker of your blood sugar levels over time, providing insight into how well your body manages glucose without daily fluctuations.
Why It’s Used in Diabetes Care
Doctors use HbA1c to assess long-term diabetes management, helping to identify trends in blood sugar control that aren’t visible from a single blood test. It’s a key tool for adjusting treatment plans, such as medication or diet.
How It’s Done
A small blood sample is taken from your arm, usually during a routine visit. The sample is processed using HPLC to measure the percentage of hemoglobin bound to sugar, with results reported as a percentage.
What Normal Results Mean
While reference ranges vary by lab, HbA1c results are often categorized into general health categories (e.g., normal, prediabetes, diabetes) rather than specific numeric ranges. Your doctor will interpret results in the context of your health and treatment goals.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
HbA1c is critical for diagnosing diabetes (typically ≥6.5%) and monitoring prediabetes (4.5%–5.9%). It also helps detect complications like nerve damage or kidney issues by revealing chronic blood sugar exposure. Some conditions (e.g., anemia) can affect HbA1c, so results should be discussed with your provider.
Short name
HbA1c
Frequently asked questions
How often should I get an HbA1c test?
Can HbA1c results change if I’ve recently eaten or exercised?
What if my HbA1c is higher than expected?
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