Skip to content

Hemoglobin A1c (Glycated Hemoglobin) with Mass Fraction Measurement

Published: August 9, 2026Updated: August 16, 2026

This test measures the percentage of hemoglobin in your blood that is attached to sugar (glycated hemoglobin), reflecting your average blood sugar levels over the past 2–3 months.

Quick summary

["Helps track long-term blood sugar control for diabetes management."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
54072-4
Short code
Hgb A MFr DBS
Synonyms
Hgb A 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 Is HbA1c Used For?

HbA1c is primarily used to diagnose diabetes and monitor long-term blood sugar levels. It provides a snapshot of how well your body manages glucose over time, which can help adjust treatment plans if needed.

How Is This Test Performed?

A small blood sample is taken from your arm, usually during a routine visit to your healthcare provider. The test measures the proportion of hemoglobin molecules that have sugar molecules attached, indicating average blood sugar levels.

Why Is HbA1c Important?

Regular HbA1c testing helps prevent complications from high blood sugar, such as nerve damage, kidney disease, or vision problems. It’s a key tool for managing diabetes and prediabetes.

What Does an Abnormal Result Mean?

Results outside typical ranges may signal poor blood sugar control. For example, higher-than-normal levels could indicate diabetes or inadequate treatment, while lower levels might suggest hypoglycemia or other conditions.

Reference range

Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A

Specimen: serum

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.

◆Associated findings1

Short name

HbA1c Mass Fraction

Frequently asked questions

How often should I get an HbA1c test?
Typically, people with diabetes get tested every 2–3 months, while those at risk for prediabetes may need testing every 6 months. Your doctor will determine the best schedule based on your health status.
Can lifestyle changes affect HbA1c results?
Yes! Improving diet, exercise, and managing stress can lower HbA1c levels over time. Conversely, poor dietary habits, lack of activity, or smoking may raise it. Small, consistent changes often make the biggest difference.
Is HbA1c the same as a fasting blood sugar test?
No. HbA1c measures average blood sugar over months, while fasting blood sugar tests check current blood glucose levels after an overnight fast. Both are important, but HbA1c provides a broader picture of long-term health.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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