Human intestines vary in length but generally measure as follows:

• The small intestine is the longest part of the intestines, typically ranging from about 9 to 16 feet (approximately 3 to 5 meters) in length. It consists of three parts: the duodenum (about 8 to 10 inches), the jejunum (around 8 feet), and the ileum (close to 10 feet), with the ileum being the longest section

• The large intestine is shorter, roughly about 5 feet (1.5 meters) long. It includes the cecum, colon (the longest portion), rectum, and anus. The large intestine is wider in diameter than the small intestine

Together, the small and large intestines combine to a total length of about 15 to 20 feet (approximately 4.5 to 6 meters), with some individual variation

. Despite the small intestine's name, it is called "small" due to its diameter (about 1 inch or 2.5 cm), not its length

. In summary, human intestines are approximately:

• Small intestine: 9–16 feet (3–5 meters)
• Large intestine: about 5 feet (1.5 meters)
• Total combined length: roughly 15–20 feet (4.5–6 meters)