What is a complete blood count (CBC)?

A complete blood count, or CBC, measures the number of red blood cells, white blood cells, and platelets in your blood. It also measures hemoglobin (the protein that carries oxygen) and other details about your red blood cells.

According to the National Cancer Institute, the CBC is often part of a routine check-up. It can help diagnose some cancers, especially leukemias, and it is also used to monitor your health during and after treatment.

As with all lab tests, a CBC is read alongside your other results, and your doctor is the best person to explain what it means for you.