An average adult that weighs approximately 150 pounds will have about 186 ounces of total blood volume. Children that are about 80 pounds will have about 93 ounces, or half the amount of an adult.The amount of blood that the human body contains is about 7 percent of its weight.
Blood amounts in humans can vary according to age, sex, size and weight. In general, men can have more blood than women even in those who are of the same size and weight.
Blood consists of different components, such as red blood cells, white blood cells and platelets. Each of these components plays a vital role in the human body. While red blood cells transport oxygen to the entire body, white blood cells are a part of the immune system that help to protect the body from infections and bacteria. Platelets are involved in the blood clotting process.