Skip to content

Complete Blood Count with Differential (CBC with Differential)

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

This test measures the types and amounts of cells in your blood, including red blood cells, white blood cells, and platelets, along with the proportions of different white blood cell types (differential count).

Quick summary

["Understanding your blood cell composition can help identify infections, anemia, or other health conditions."]

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

Key facts at a glance

LOINC
19762-4
Short code
Gen Categ Cvx/Vag Cyto-Imp
Synonyms
Gen Categ Cvx/Vag Cyto-Imp
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
cyto-stain
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 Does a CBC with Differential Measure?

A CBC with differential includes several key components: - **Red Blood Cells (RBCs):** Count and size (mean corpuscular volume, MCV). - **White Blood Cells (WBCs):** Total count and breakdown of subtypes (neutrophils, lymphocytes, monocytes, eosinophils, basophils). - **Platelets:** Count and size (mean platelet volume, MPV).

Why Might You Need This Test?

This test is commonly ordered to diagnose or monitor conditions like infections, anemia, blood disorders, or immune system issues. It can also help track responses to treatments or screen for hidden health problems.

How Is the Sample Collected?

A small amount of blood is drawn from a vein, usually in your arm, using a needle. The sample is sent to the lab for analysis. You may feel a brief pinch, but the procedure is quick and typically painless.

What Does the Differential Count Tell Us?

The differential count helps identify the specific types of white blood cells present. For example: - **High neutrophils** may indicate bacterial infection. - **High lymphocytes** could suggest viral infection or chronic conditions. - **Abnormal counts** may signal immune disorders or other systemic issues.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

CBC with Differential

Frequently asked questions

What Are Common Results to Watch For?
A CBC with differential can reveal subtle shifts in blood health that might not be obvious from a standard CBC alone. For instance, an elevated or low white blood cell count, unusual proportions of cell types, or abnormal platelet levels may signal underlying health concerns that require further investigation.
How Long Does It Take to Get Results?
Results are usually available within 1 to 3 business days, depending on lab processing times. Your healthcare provider will discuss the findings with you during your follow-up visit.
Can I Eat or Drink Before This Test?
You can eat and drink normally before the test unless instructed otherwise by your doctor. No special preparation is needed for a standard CBC with differential.
  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