The total blood volume in the human body varies depending on factors such as age, sex, weight, and overall health. On average, an adult human body contains about 4.5 to 6 liters (approximately 1.2 to 1.6 gallons) of blood. This estimate is usually given as a percentage of body weight, and blood typically makes up about 7-8% of a person's total body weight.
For example, in a healthy adult with a body weight of 70 kilograms (154 pounds), their blood volume would be around 5.5 liters (1.45 gallons). However, keep in mind that these values can vary, and individual differences are normal.
It's important to note that blood volume can also change during certain conditions, such as pregnancy or dehydration, and it can be affected by medical conditions or treatments. Always consult with a healthcare professional if you have specific concerns about blood volume or related health issues.