The 10 Largest Octopuses in the World

Equally mysterious and beautiful, octopuses are captivating creatures. There are over 300 octopus species, and they thrive in every ocean habitat. Their soft bodies can rapidly change shape, shifting from small to large within moments. Their nervous system and brain function are among the most complex found in any invertebrate. Octopuses come in all shapes and sizes, but which type is the biggest octopus in the world? On examining their length and weight, it’s easy to determine which of these eight-limbed cephalopods is the largest of them all. Here are the 10 largest octopuses in the world. 

#10: Dumbo Octopus

The Dumbo octopus (Grimpoteuthis) gets its name from Disney’s famous character due to its large fins that resemble the elephant’s ears. While the average Dumbo octopus measures between 7.9-12 inches long, some can grow to be much larger. The largest recorded specimen was five feet and 10 inches long and weighed almost 13 pounds. There are more than 15 species of Dumbo octopus. They are the deepest-dwelling octopus, living at depths of at least 13,100 feet in tropical and temperate waters worldwide. Additionally, they do not have an ink sac, as they have few natural predators so deep in the ocean. The IUCN currently lists the dumbo octopus as a species of Least Concern.

#9: Southern Red Octopus

Also known as the Patagonian red octopus, the southern red octopus (Enteroctopus megalocyathus) belongs to the genus of giant octopus. Although they are not as massive as other species of Enteroctopus, the southern red octopus can still reach impressive sizes. Their average weight is 8.8 pounds, and they usually measure around 3.3 feet in length. Southern red octopuses are distinguishable by their striking red color and paddle-shaped papillae. They are native to the coasts of Chile and Argentina, where they are one of the most abundant species of octopus. Currently, the IUCN has yet to evaluate the status of the southern red octopus.

#8: Yellow Octopus

The yellow octopus (Enteroctopus zealandicus) is another member of the genus of giant octopuses. Little information exists about these mysterious creatures, so scientists must estimate how big they can grow. To date, the largest yellow octopus weighed 11 pounds and measured 4.6 feet in length. Yellow octopuses live in the deep waters surrounding New Zealand at around 980-1700 feet. Although they are abundant, few specimens have ever been recovered. The IUCN has not yet evaluated the status of the yellow octopus. 

#7: Mimic Octopus

The mimic octopus (Thaumoctopus mimicus) is one of the most extraordinary varieties of octopus in the ocean. They are sexually dimorphic, as the females are much larger than the males. While males typically weigh between 5-6 pounds, females can easily weigh up to 20 pounds. The average length of a male mimic octopus is around two feet, but females are around six feet. Many species can camouflage their bodies, but mimic octopuses can take on the appearance of multiple different toxic creatures. This is called dynamic mimicry. They are found in the shallow waters of the Indo-Pacific, primarily near Indonesia. To date, the IUCN has not evaluated the status of the mimic octopus. 

#6: Common Octopus

In addition to being one of the largest known species, the common octopus (Octopus vulgaris) is also considered the most intelligent invertebrate in the world. The common octopus has a number of techniques to avoid predators. They can camouflage themselves in their surroundings, use ink to obscure their movements, squeeze through any hole larger than their beaks, and even sacrifice an arm to escape, as it will grow back. They can grow as large as 4.3 feet in length and weigh up to 22 pounds. While common octopuses reside in all temperatures of waters all over the world, they congregate in relatively shallow, rocky areas near coasts. The IUCN lists the common octopus as a species of Least Concern.

#5: Southern Giant Octopus

Similar to other members of the genus Enteroctopus, the southern giant octopus (Enteroctopus magnificus) is known for its distinctive size. Specimens typically weigh around 25 pounds and can measure up to six feet in length. They are native to the waters off the coasts of Namibia and South Africa and tend to enjoy spending time in shallow, sub-tidal areas. Southern giant octopuses hunt a wide variety of prey, but their diet primarily consists of deep-sea portunid crabs. The IUCN has not yet evaluated the status of the southern giant octopus.

#4: Maori Octopus

Also known as the New Zealand octopus, the Maori octopus (Macroctopus maorum) is just slightly larger than the southern giant octopus. On average, they weigh between 22-26.5 pounds and measure from 3.3-6.5 feet in length. Maori octopuses are famously aggressive compared to other species of octopus. Females can lay up to 7,000 eggs at a time and will fiercely protect their spawn from predators. They are predominantly located in the waters surrounding South Australia and New Zealand. Currently, the IUCN has not evaluated the status of the Maori octopus, although the population appears to be stable based on catch records. 

#3: Frilled Giant Pacific Octopus

Discovered in 2017, the frilled giant Pacific octopus is a close relative of the giant Pacific octopus. They do not yet have their own scientific name as they have not been formally established as a separate species. The frilled giant Pacific octopuses are distinguishable from their sister species thanks to a frill of merged papillae across their bodies, along with two white spots on their heads. Little information is available about their average size, but biologists estimate that they can reach up to 110 pounds and 16 feet in length. They can be found around Prince William Sound on the south coast of Alaska. The IUCN has yet to evaluate the frilled giant Pacific octopus’s status. 

#2: Seven-Arm Octopus

Although its name is somewhat misleading, the seven-arm octopus (Haliphron atlanticus) has eight arms like all other species of octopus. Their name comes from the unique arm used for egg fertilization that is coiled in a sac beneath the male’s right eye. Among known octopuses, they are second only to the giant Pacific octopus in terms of size. They can reach a maximum weight of 165 pounds and lengths of around 11 feet. The majority of specimens originated from the Atlantic Ocean, but rare sightings have occurred in the South Pacific. The IUCN lists the seven-arm octopus as a species of Least Concern. 

#1: Giant Pacific Octopus

The giant Pacific octopus (Enteroctopus dofleini) is the largest species of octopus in the world. They typically weigh around 150 pounds and measure over 15 feet long. However, the largest specimen on record weighed almost 600 pounds and measured 30 feet in length. Their diet consists of clams, shrimp, crabs, abalone, snails, scallops, fish, lobsters, and even other octopuses. On occasion, giant Pacific octopuses will even prey upon small sharks, such as the spiny dogfish. Sightings usually occur in waters bordering the western United States, British Columbia, Alaska, Japan, Russia, and the Korean Peninsula. The population of giant Pacific octopuses is unknown, but the IUCN currently lists them as a species of Least Concern.