White Blood Cell Count Test
The number of infection-fighting cells in your blood. Changes can reflect infection, inflammation, or marrow activity.
What is White Blood Cell Count?
The number of infection-fighting cells in your blood. Changes can reflect infection, inflammation, or marrow activity.
Find a White Blood Cell Count test
We offer panels that include this marker. Browse to find the best fit.
Browse testsWhite Blood Cell Count Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+ | 4.50 – 11.0 10^3/uL |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
What your White Blood Cell Count result may mean
Often reflects an active infection, inflammation, stress, or certain medications.
Can reflect viral infections, autoimmune conditions, certain medications, or marrow suppression.
Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
Sources
Related Blood Health biomarkers
Markers commonly tested alongside White Blood Cell Count.
Frequently asked
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