A larger-than-normal liver may be a sign of a wide range of diseases. The liver, a wedge-shaped organ on the right side of your upper abdomen, is the largest internal organ. An adult liver normally weighs between 2.6 and 3.3 pounds (1.2 to 1.5 kg) and measures an average of 5.9 inches (15 cm) in width. It's very unusual to have an enlarged liver without other signs and symptoms that point to an underlying disease. Symptoms.