Versus 3 min read
Colossal Squid vs. Giant Squid: Which Is the Biggest Squid in the World?
Two sea monsters, one crown. One is longer, one is heavier, and both have eyes the size of dinner plates. So which squid really wins?
Two monsters, one crown. The giant squid and the colossal squid are the biggest invertebrates on Earth, and both have inspired centuries of sea-monster stories. But which one is actually bigger? The answer depends on how you measure, and that’s where it gets fun.
Meet the contenders
The giant squid (Architeuthis dux) lives in oceans all over the world. It’s long, slim and built like a living whip. The colossal squid (Mesonychoteuthis hamiltoni) lives only in the icy Southern Ocean around Antarctica. It’s shorter, but much heavier and much more heavily armed.
The tale of the tape
| Giant squid | Colossal squid | |
|---|---|---|
| Longest | Around 12–13 m, mostly tentacles | Estimated up to around 10 m |
| Heaviest known | Around 275 kg | Around 495 kg |
| Eyes | Up to about 27 cm | About 27 cm or more, probably the largest of any animal |
| Weapons | Suckers lined with sharp, toothed rings | Suckers plus rotating, swivelling hooks |
| Home | Oceans worldwide | Southern Ocean only |
Round one: length
The giant squid wins this one. Its two feeding tentacles are incredibly long and stretchy, so from tip to tail it can outmeasure its colossal cousin. But a lot of that length is basically two very long pieces of spaghetti.
Round two: weight
Here the colossal squid crushes it. The heaviest one ever caught, landed in 2007, weighed around 495 kg. That’s almost twice as heavy as the biggest giant squid on record. Its body is wide and muscular, built more like a tank than a whip.
Strange but trueThe colossal squid’s eyes are the size of dinner plates, probably the biggest eyes in the animal kingdom. Scientists think they evolved to spot sperm whales coming in the dark.
Round three: weapons
Both squid have suckers, but the colossal squid takes it further: its arms and tentacles carry sharp hooks, some of which can swivel. Sperm whales, their main enemy, often carry scars from these fights.
The giant squid is the longest. The colossal squid is the biggest.
Have we seen them alive?
Barely. The first photos of a living giant squid in the wild were only taken in 2004, and it was first filmed in its deep-sea home in 2012. The colossal squid is even more secretive: the first confirmed footage of a live one in the wild, a young one about 30 cm long, was only captured in 2025.
The winner
If you’re measuring with a tape, the giant squid takes the crown for length. If you’re putting them on a scale, the colossal squid wins by a landslide. Most scientists call the colossal squid the biggest squid in the world, because size in the animal world is usually about mass. Either way, you don’t want to meet either of them in the dark.
Tell a friend
