How big is a giant squid? The best way to start is with the ones people have seen alive. People have filmed a giant squid alive in the deep sea.

On September 30, 2004, a camera on a bait line off Japan's Ogasawara Islands photographed a giant squid alive in the deep ocean. As of November 2026, the first photographs of a live giant squid in the ocean were reported in September 2005. The squid was taking bait about 900 metres (3,000 feet) down. It was about eight metres long.

In July 2012, a team filmed a live giant squid in its deep-sea home off Japan, from a small submersible. The squid was seen about 630 metres down. It was about three metres long.

In June 2019, scientists filmed a giant squid in the Gulf of Mexico. It was the first one recorded in United States waters. It was about 100 miles southeast of New Orleans. It was about 10 to 12 feet long.

A giant squid has the largest eyes in the animal kingdom, about 10 inches across. The eyes let in a lot of light, which helps the squid notice faint shapes in dim water. Sperm whales, the largest of the toothed whales, eat mostly squid. A giant squid's eyes may help it see a sperm whale coming. A moving whale makes tiny sea animals glow. Scientists estimate a giant squid could notice that glow from about 120 meters away.

A giant squid has eight arms and two longer feeding tentacles. The tentacles are much longer than the rest of its body. At the base of its arms is a hard, parrot-like beak.

Much of what scientists know about giant squid comes from animals washed up on beaches and from parts found in whales. DNA gives more answers. In March 2013, scientists reported that DNA from giant squid around the world shows they are one species. They live in all of the world's oceans.

Words to know

• tentacles: long feeding arms
• submersible: small sea vehicle
• species: kind of animal
• beak: hard mouth