how much blood is in the human body

The human body typically contains about 4.5 to 6 liters of blood, which corresponds to approximately 7-8% of an adult's total body weight. The exact amount can vary depending on factors like age, weight, sex, and physiological conditions such as pregnancy. For example, pregnant women may have 30-50% more blood volume to support the fetus. Infants and children have proportionally more blood relative to their body weight, with infants having about 9-10% and children 8-9% of their body weight in blood. Adults generally have around 5 liters, with men tending to have slightly more blood volume than women due to differences in body size and composition. This volume equates roughly to 10 to 12 pints of blood in the average adult body.