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Hemoglobin A1c (HbA1c) with Mass Concentration Measurement

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

This test measures the average level of hemoglobin A1c in your blood over the past 2–3 months, reflecting your long-term blood sugar control.

Quick summary

["HbA1c helps doctors assess how well your diabetes is managed over time."]

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

Key facts at a glance

LOINC
54289-4
Short code
Hgb Bld BPU-mCnc
Synonyms
Hgb Bld BPU-mCnc
Category
hematology
Sample
whole-blood
Container
Lavender-top (EDTA)
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
3 mL
Stability
Room temperature: 4h, Refrigerated: 24h
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

Why This Test Matters

HbA1c is a key indicator of how well your body manages glucose (sugar) levels, even if your current blood sugar readings are normal. It’s often used to diagnose diabetes, monitor treatment effectiveness, and prevent complications like nerve damage or heart disease.

How It’s Performed

A small blood sample is taken from your arm, usually via a simple fingerstick. The test measures the percentage of hemoglobin molecules that are bound to glucose, providing a snapshot of your average blood sugar over time.

What It Can Tell You

A higher HbA1c level suggests poor blood sugar control, while a lower level may indicate better management. However, individual results depend on factors like diet, activity, and medications.

What to Expect Before or After

No special preparation is needed, but you may feel slight discomfort from the needle. Results are typically ready within 24–48 hours and shared with your healthcare provider.

Reference range

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

Specimen: whole-blood

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

Frequently asked questions

What does an abnormal HbA1c result mean?
An elevated HbA1c (typically ≥6.5%) often signals diabetes or prediabetes, prompting lifestyle changes or medication adjustments. A lower result (below 5.7%) may indicate good control, but ongoing monitoring is still important.
How often should I get this test?
If you have diabetes, your doctor may recommend testing every 3–6 months. For prediabetes or pre-diagnosed risk, testing every 1–2 years may suffice, but follow your provider’s guidance.
Can diet or exercise affect HbA1c results?
Yes! Consistent blood sugar management through diet, exercise, and medications can lower HbA1c levels. However, results reflect your average over time, so short-term fluctuations won’t immediately change the test result.
  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