A normal range in adults is generally considered to be 4.35 to 5.65 million red blood cells per microliter (mcL) of blood for men and 3.92 to 5.13 million red blood cells per mcL of blood for women. In children, the threshold for high red blood cell count varies with age and sex.

What does RBC in the blood mean?

A red blood cell (RBC) count measures the number of red blood cells, also known as erythrocytes, in your blood. Red blood cells carry oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, reproduce, and stay healthy.

What does a low RBC mean?

A low red blood cell count means you have anemia, a condition that could be caused by a variety of factors like blood loss, genetic disorders, cancer treatments and other causes. Discovering anemia is often the starting point to diagnosing an underlying condition. Red blood cells carry oxygen in the blood.