Learn what each component of your Complete Blood Count test means and what normal ranges look like.
What is a CBC Test?
A Complete Blood Count (CBC) is one of the most common blood tests ordered by doctors. It gives important information about the kinds and numbers of cells in the blood, especially red blood cells, white blood cells, and platelets.
Components of CBC
Red Blood Cells (RBC)
Red blood cells carry oxygen from your lungs to the rest of your body. Normal range for adults: Men 4.5–5.5 million/μL, Women 4.0–5.0 million/μL.
White Blood Cells (WBC)
White blood cells help fight infection. Normal range: 4,500–11,000 cells/μL.
Hemoglobin
Low hemoglobin indicates anemia. Normal: Men 13.5–17.5 g/dL, Women 12–15.5 g/dL.
Platelets
Platelets help with blood clotting. Normal range: 150,000–400,000/μL.