Surf's Up Magazine

Octopus vs Squid: All you need to Know

  • Date: February 27, 2024
  • Time to read: 6 min.

Do you know the difference between an octopus vs squid? It’s easy to confuse them both given that they have eight arms, remarkable intelligence, and can shoot ink from their sacs for self-defense. Appearances aside, however, there are a few notable distinctions which set these cephalopods apart.

Do octopi and squids truly differ? To find out, why not try a serving of calamari or octopus tentacles at your favorite restaurant?

After the first bite, you will quickly learn that these ancient marine dwellers have distinct characteristics unlike any other. With just one dish, you can recognize their vast differences!

This article will explore the difference between octopus vs squid in 8 distinct categories. Thus giving readers the knowledge they need to easily differentiate between these two species. Additionally, we’ll answer some of the most common queries regarding both creatures!

octopus vs squid

The Main Differences Between Squid vs Octopus

Below you’ll find the main differences between these two molluscs.


Although, generally speaking, there is not much disparity in size between octopus and squid species, more diversity can be observed at the ends of the spectrum. Octopus wolfi holds the title for smallest octopod with a body length barely 1 inch long and weighting an imperceptible gram.

The giant Pacific octopus may be extraordinary, reaching up to 30 feet and nearly 600 pounds in weight. However, when compared with the smallest or largest squid species, this difference is instantly discernible.

To illustrate, the Thai bobtail squid is the littlest known cephalopod, measuring less than 0.5 inches long and clocking in at under one gram. Comparatively speaking, we have giant squids which can reach up to 45 feet in size and weigh more than a ton!

Despite octopus’ average larger sizes when compared to squids’, there’s no denying that they cover an enormous range of size variations. From miniscule bobtails to gargantuan giants!

Octopus vs Squid: Shape of Head

Octopuses and squids are both head-footed creatures, where the majority of their organs are safely encased in a mantle.

However when seen side by side, an obvious difference can be observed in regards to their mantles and heads. An octopus’s heralds a much more rounded form with its round mantle and bulbous like head shape.

From a variety of colors and patterns, to camouflage that mirrors their natural habitat. Octopi have mastered the art of disguise. With one exception: the Dumbo Octopus living in extreme depths – none possess fins on their mantle.

In contrast, squids possess a triangular-shaped mantle. Not like octopuses, squid flaunt minuscule fins on either side of their mantle that they use for locomotion and guidance. Furthermore, the motifs and shades of squid have a tendency to be more subdued than other sea creatures in its class. However, when threatened they are able to camouflage themselves instantly.

how many suction cups does an octopus have
Octopus Head

Squid vs Octopus: Habitat

When it comes to their living environment, octopuses and squid have several distinctions. Generally speaking, the former can be found near the seabed; they construct their habitats in coral reefs, around coastlines and on the ocean floor of both shallow waters and deep-sea depths.

While a few species of octopus defy the norm and reside in open waters, most prefer to remain near the ocean floor. However, squids are abundant in both surface level areas and deep sea depths since they don’t construct dens like their cephalopod counterparts. Making them free to explore all corners of the oceans.


One of the ways to discern between an octopus and a squid is by examining their arms. On first glance, they may appear similar; however, if you take time to inspect further, significant distinctions become apparent. Generally speaking, an octopus’s appendages feature one or two rows of suckers; yet those suction cups don’t have rings or hooks at their tips like squids do!

With their powerful arms, squids can capture and sustain prey as well as move along the ocean floor. Depending on the species, these limbs may be lined with sucker rings or even small hooks that aid in capturing wriggling food items. The evolution of such structures further demonstrates just how adaptive and resourceful squid are. This makes them a special part of our underwater ecosystem!

The major distinction between the two is that squids have two lengthy tentacles. Through their tentacles, they grab their prey and utilize all eight arms to firmly secure food while consuming it.

humboldt squid on shore
Squid Arms

Octopus and Squid: Diet

Apart from the diverse way they manipulate their food-grabbing appendages, octopuses employ their arms while squids use tentacles to get hold of prey, then switch over to using their arms for holding it in place. There are several other disparities between an octopus’ and squid’s dieting habits.

Octopuses feast on a variety of crustaceans such as crabs, clams and whelks for sustenance. For bigger species, fish and shrimp are also included in their diet. After capture, they take the prey back to their hideaway where venomous saliva is injected via their powerful beaks into the food source before consumption.

The saliva of an octopus comes in handy when it’s time to feed, as it paralyzes their prey and dissolves any hard shells. This grants the creature access to the succulent inner flesh they crave. On the other hand, squids opt for a more aggressive approach; using their powerful beaks, they rip apart shrimp and small fish before taking large chunks of meat into their mouths.


The lifespans of octopuses and squids can differ drastically, based on the species. In general, most octopuses and squids pass away just after mating – meaning that they are only able to experience life until reaching reproductive maturity and securing a chance to mate.

Despite similar lifespans, squids tend to outlive octopuses in the wild. On average, an octopus lives between 1 and 3 years with reports of some living up to 5 years or as short as 6 months.

Squids again have a wide variation ranging from just 9 months all the way up to 15 years! Most species are reported to live between 1-5 year mark though – giving them that extra edge over their cephalopod peers.

octopus suction cups
Octopus Suction Cups

Octopus vs Squid: Socializing

For decades, octopuses and squids were thought of as loners since they largely live solitary lives – excluding mating season. Nevertheless, recent evidence has revealed that this is only part of the story. Though it’s true many species gravitate towards living alone, some have been seen interacting with others in fascinating ways!

Contrary to what was earlier believed, octopuses can live in tight-knit communities and even share their dens with other creatures. Some species of these cephalopods will also go so far as to help fish hunt cooperatively. Meanwhile, squids are becoming known for exhibiting much more social behavior than ever before understood.

Not all squids are loners; in fact, some species such as bigfin reef squid tend to congregate. Furthermore, studies suggest that cephalopods can even converse with each other! For example, Humboldt squid have been observed displaying bright colors and flashes of light to communicate between one another.

Octopus and Squid: Reproduction

When it comes to parenting, octopus are unrivaled versus squid. Octopuses have a specialized arm that males use called the hectocotylus which effectively deposits sperm into the female’s mantle cavity and fertilizes her eggs. This efficient process makes them stand out as outstanding parents compared to their cephalopod counterparts!

When it comes to reproduction, female mammals will typically lay their eggs in a den and tenaciously protect them until birth. In certain situations, they’ll even construct walls or barricades against possible attackers. Meanwhile, squids reproduce collectively either through a hectocotylus or by the “head-to-head” technique.

Instead of protecting their eggs, female sea creatures choose to anchor them to rocks or seaweed. Others don’t even have the need for a stable surface and opt instead to leave their eggs adrift in the expansive ocean until they are ready to hatch.

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