What is the approximate length of human small intestine?

Although the small intestine is narrower than the large intestine, it is actually the longest section of your digestive tube, measuring about 22 feet (or seven meters) on average, or three-and-a-half times the length of your body.

The small intestine is a long tube that's about 1½ inches to 2 inches (about 3.5 to 5 centimeters) around, and it's packed inside you beneath your stomach. If you stretched out an adult's small intestine, it would be about 22 feet long (6.7 meters) — that's like 22 notebooks lined up end to end, all in a row!

The small intestine breaks down the food mixture even more so your body can absorb all the vitamins, minerals, proteins, carbohydrates, and fats. The grilled chicken on your pizza is full of proteins — and a little fat — and the small intestine can help extract them with a little help from three friends: the pancreas , liver, and gallbladder.