The Average IQ of an Octopus: How Smart Are They?

The distributed brain: eight arms that think

The single most important fact about octopus intelligence is where the thinking happens. Of the roughly 500 million neurons in a common octopus, only about a third sit in the central brain. The other two-thirds are spread through the eight arms, each of which carries its own dense cluster of nerve cells — effectively eight "mini-brains" wired around a central one.

This is not a metaphor. Studies of octopus neuroanatomy show that an arm can process touch and taste and decide how to grasp or explore an object largely on its own, while the central brain issues something closer to a general instruction like "find food" than a precise motor command. A neural ring even lets the arms pass information to one another without the central brain necessarily being in the loop.

That architecture is a genuinely different kind of mind. Human intelligence is centralized: one brain runs the show. Octopus intelligence is decentralized and distributed, which is likely how the animal manages eight boneless, infinitely flexible limbs with no fixed joints or body plan. When you compare an octopus to a dog by neuron count alone, you miss the headline — the same rough hardware budget is organized in a completely alien way.

The real evidence: what octopuses actually do

The impressive part is not that octopuses are cute. It is that careful researchers have documented behaviors that meet strict scientific bars.

Tool use. In a 2009 study published in Current Biology, biologist Julian Finn and colleagues watched veined octopuses (Amphioctopus marginatus) dig up discarded coconut-shell halves, clean them, tuck them under their bodies, and "stilt-walk" across open seabed carrying them — awkward, exposed, and slower than normal — only to reassemble the shells into a shelter later. That delayed payoff is exactly what qualifies it as tool use, and it was the first such case ever documented in an invertebrate. The octopus gains nothing while carrying the shell; the whole point is the future.

Jar-opening and puzzle-solving. Captive octopuses routinely learn to unscrew jars to reach food inside, and can solve the problem even when the jar is closed from within. In aquariums they work through mazes and puzzle boxes, adjusting their approach across trials rather than repeating a fixed reflex.

Escapes. Because an octopus has no bones, it can pour its entire body through any gap large enough for its beak — the only hard part of its anatomy. Combine that flexibility with curiosity and memory, and you get the famous escape stories: octopuses slipping out of tanks at night, and in one widely reported case, a New Zealand aquarium octopus named Inky who squeezed out of his enclosure and down a drainpipe to the sea.

Play and personality. Cephalopod researchers Jennifer Mather and Roland Anderson gave octopuses floating pill bottles and found that some individuals repeatedly blew water jets at them, batting the bottle away and letting the current carry it back — behavior that fits the scientific definition of play, doing something for no immediate reward. They also found large, consistent differences between individuals: a factor analysis pulled out dimensions they labeled Activity, Reactivity, and Avoidance, accounting for a large share of the variation. In plain terms, octopuses have personalities. Some are bold, some shy, some grumpy — and they stay that way.

The honest bottom line

So how smart is an octopus? Smart enough to solve problems, plan a little, learn from experience, play, and act like an individual — the gold standard for invertebrate cognition, and comparable in raw neural hardware to a dog. But "average IQ of an octopus" is the wrong frame, and any specific number you see attached to it (an "octopus IQ of X") is invented, not measured. No validated test produces one, because no test could.

The more interesting truth is that the octopus shows us intelligence is not one thing on a single ladder with humans at the top. It evolved a completely separate route to a capable mind — distributed across the body, alien in structure, and roughly as ancient a split from our lineage as animal brains get. Curious how the human version of this question is measured? A real IQ test is standardized against thousands of people so your score has meaning relative to others.

FAQ

Q: What is the average IQ of an octopus?

A: There isn't one. IQ is a human-standardized score with a mean of 100, and no validated test measures it in an octopus. Researchers instead assess octopus intelligence through problem-solving, tool use, learning, and observed behavior — where octopuses rank as the smartest invertebrates known.

Q: How many neurons does an octopus have?

A: About 500 million, roughly comparable to a dog. The striking part is the layout: around two-thirds of those neurons sit in the eight arms rather than the central brain, giving each arm a degree of independent processing.

Q: Are octopuses smarter than dogs?

A: They are hard to compare directly. Their neuron counts are in a similar range, but the architecture is completely different — centralized in a dog, distributed across the body in an octopus. Octopuses excel at manipulation, escape, and problem-solving; dogs excel at social and human-directed tasks. "Smarter" depends entirely on the task.

Q: Do octopuses really use tools?

A: Yes, by the strict scientific definition. A 2009 study documented veined octopuses carrying coconut-shell halves to assemble as shelter later — the first confirmed case of tool use in any invertebrate, because the benefit is delayed rather than immediate.

References

• Finn, J. K., Tregenza, T., & Norman, M. D. (2009). Defensive tool use in a coconut-carrying octopus. Current Biology, 19(23), R1069–R1070. https://www.cell.com/current-biology/fulltext/S0960-9822(09)01914-9
• Mather, J. A., & Anderson, R. C. (1999). Exploration, play, and habituation in octopuses (Octopus dofleini). Journal of Comparative Psychology, 113(3), 333–338. https://www.researchgate.net/publication/232525177_Exploration_Play_and_Habituation_in_Octopuses_Octopus_dofleini
• Godfrey-Smith, P. (2016). Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness. Farrar, Straus and Giroux.

Last updated: July 13, 2026