The largest organ in the human body is the skin. It is an external organ that covers the entire body, weighing about 8 pounds (approximately 4,535 grams) and covering around 22 square feet in an average adult
. The skin serves as a crucial barrier protecting the body from bacteria, chemicals, and temperature changes, and it also plays roles in sensation, temperature regulation, and vitamin D synthesis
. Among internal organs, the largest solid organ is the liver, which weighs about 3 to 3.5 pounds (1.36 to 1.59 kilograms) and is roughly the size of a football. The liver is located in the upper right abdomen beneath the rib cage and lungs and performs vital functions such as filtering toxins from the blood, producing bile, making blood plasma proteins, storing glycogen, and managing blood clotting
. Other large internal organs include the brain (about 3 pounds), lungs (about 2.2 pounds combined), heart (about 11 ounces), and kidneys (each about the size of a small fist)
. There is emerging research suggesting that the interstitium-a network of fluid-filled spaces supported by connective tissue throughout the body-might be considered an organ and potentially the largest organ if accepted by the medical community. However, this is not yet widely recognized and requires further study
. In summary:
- Largest organ overall: Skin (external, ~8 pounds)
- Largest solid internal organ: Liver (~3-3.5 pounds)
- Other large internal organs: Brain, lungs, heart, kidneys
This ranking can vary slightly depending on individual factors like age, gender, and body size
Summary Table
Organ| Approximate Weight| Notes
---|---|---
Skin| ~8 pounds (4,535 g)| Largest organ overall, external
Liver| 3-3.5 pounds (1,360-1,590 g)| Largest solid internal organ
Brain| ~3 pounds (1,360 g)| Controls body functions
Lungs| ~2.2 pounds (1,000 g)| Oxygenate blood
Heart| ~11 ounces (300 g)| Pumps blood
Kidneys| ~260 g (pair)| Filter blood and produce urine
Thus, the skin holds the title as the largest organ in the human body.
