9 Largest Octopus Species Lurking in the Deep Blue Sea

Octopuses are cephalopods that have three hearts and eight arms that are covered with suckers. The largest octopus is the giant Pacific octopus. As its name suggests, the Giant Pacific Octopus lives in the North Pacific Ocean.

Bigger octopuses generally tend to live longer than smaller octopuses. They also tend to live in colder, deeper waters (making them harder to spot) than their smaller counterparts, and they can hunt larger prey.

Let's take a look at the biggest octopus species in the world, starting with the king of them all.

Contents

Giant Pacific Octopus (Enteroctopus dofleini)
Seven-Arm Octopus (Haliphron atlanticus)
Frilled Giant Pacific Octopus (Enteroctopus dofleini frilled)
North Pacific Giant Octopus (Enteroctopus dofleini borealis)
Maori Octopus (Macroctopus maorum)
North Atlantic Giant Octopus (Enteroctopus spp.)
California Two-Spot Octopus (Octopus bimaculoides)
Southern Red Octopus (Enteroctopus megalocyathus)
Common Octopus (Octopus vulgaris)

1. Giant Pacific Octopus (Enteroctopus dofleini)

The largest octopus species is the adult giant Pacific octopus, with the largest individual ever recorded weighing 600 pounds (272 kilograms) and having a 30-foot (9-meters) arm span.

On average, the giant Pacific octopus weighs around 150 pounds (68 kilograms) and measures up to 20 feet (6 meters) across.

These intelligent octopuses have one central brain — plus mini-brains in each of their eight arms — allowing them to solve puzzles, open jars and even recognize human faces.

Environment, Diet and Dangers

The giant Pacific octopus spends most of its time in the cold waters of the Pacific Ocean, from California to Japan. It is known for its incredible camouflage, as it can change color and texture to blend with its surroundings.

This octopus' diet includes crustaceans, fish and even small sharks. (Yes, you read that right: They can eat sharks!) With their powerful suckers and parrot-like beak, they can break through tough shells and devour a wide range of marine life.

This species is commercially fished in some areas, but it remains abundant thanks to its rapid growth and high reproductive rate. Female giant Pacific octopuses can lay up to 100,000 eggs, guarding them on the ocean floor until they hatch.

2. Seven-Arm Octopus (Haliphron atlanticus)

Seven-armed octopus. Gerard Soury / Getty Images

Despite its name, this octopus does have eight arms. But one is tucked away, giving it the appearance of having only seven.

The largest-recorded seven-arm octopus was 11 feet (3.5 meters) and 165 pounds (75 kilograms). It is rarely seen because it lives in the deep ocean, but scientists believe it preys on jellyfish and other soft-bodied animals.

3. Frilled Giant Pacific Octopus (Enteroctopus dofleini frilled)

A close relative of the giant Pacific octopus, this subspecies has distinctive frilly skin along its arms. It inhabits the deeper parts of the Pacific Ocean and shares many of the same traits as its larger cousin, including high intelligence and powerful hunting skills.

Its average size is 110 pounds (50 kilograms) and 16 feet (4.9 meters) across.

4. North Pacific Giant Octopus (Enteroctopus dofleini borealis)

Northern Pacific octopus. Mauricio Handler / Getty Images

Another variation of the giant Pacific octopus, this species is slightly smaller but still massive. On average, it weighs 44 to 110 pounds (20 to 50 kilograms) and has an arm span of 16 feet (5 meters).

It prefers deeper waters and is less commonly observed by divers. Like other species in its family, it uses camouflage and quick escapes to avoid predators.

5. Maori Octopus (Macroctopus maorum)

Native to the waters around Australia and New Zealand, this species can reach lengths of around 9.8 feet (3 meters).

It is a fast and powerful hunter, feeding on crustaceans and fish. Its ability to change color rapidly makes it one of the ocean's most elusive predators.

6. North Atlantic Giant Octopus (Enteroctopus spp.)

This lesser-known giant octopus is found in the North Atlantic and can grow up to 8 feet (2.4 meters) long.

It prefers colder waters and, like other species, uses a combination of camouflage and intelligence to survive. It is closely related to the giant Pacific octopus.

7. California Two-Spot Octopus (Octopus bimaculoides)

Named for the two distinctive blue spots near its eyes, this species can reach about 6 feet (1.8 meters) in length.

It is often found in shallow coastal waters along the Pacific coast and is commonly studied for its intelligence. It can recognize patterns, navigate mazes and solve puzzles.

8. Southern Red Octopus (Enteroctopus megalocyathus)

This species is found in the cold waters off South America. Southern Red Octopus are not a big as the giant octopus species, but they can reach up to 3.2 feet (1 meter) in length.

Like other octopus species, it is a master of disguise and uses jet propulsion to escape predators. Its diet consists of crustaceans and small fish, making it an important part of the marine ecosystem.

9. Common Octopus (Octopus vulgaris)

The common octopus can reach up to 3 feet (10 meters) in length and is found in tropical and temperate oceans around the world. It is highly intelligent, capable of using tools and is often studied for its problem-solving abilities.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.