The 15 Largest Ocean-Dwelling Animals

The 15 largest ocean-dwelling animals are massive in scale, but usually kind of docile when it comes to interactions with humans.

Blue Whale

Apart from the dinosaurs, this whale is the biggest animal that has ever existed. Imagine a Boeing 737 with fins and a 4-ton tongue.

Fin Whale

It’s not just the second largest animal in the sea, this whale is the second largest in the world. Despite its size, it can reach speeds of up to 23 mph.

Whale Shark

It’s easy to think that a lot of people might freak out if this shark came swimming up to them. But thankfully, this filter feeder is rather docile.

Sperm Whale

Watching one of these whales come up from the water is amazing. They are a little more aggressive than other whales, and unlike other whales, they do have teeth.

Giant Manta Rays

The pectoral fins of this massive ray can spread up to 30 feet in width. Just imagine seeing this ray gliding by from beneath.

Lion’s Mane Jellyfish

Imagine a jellyfish that has eight groups of tentacles that can reach up to 120 feet in length. Now imagine a bunch of these in a given area. Yeah, that’s terrifying.

Killer Whale

Also known as an orca, the killer whale is a predator without question. They’re also an apex predator, meaning that they don’t worry about much other than getting a bite to eat when they feel the need.

Great White Shark

Despite having one of the worst reputations in the world when it comes to being dangerous, the great white is still impressive. It’s like a giant eating machine that doesn’t stop. Thankfully, they don’t care for humans much.

Giant Oarfish

In a big way, this looks like a giant serpent. Reaching out to 56 feet in length, it’s kind of intimidating when seen in the water.

Japanese Spider Crab

These things look like a kaiju from the movies. They tend to reach around 12 feet in width and have insanely long claws and pincers.

Ocean Sunfish

It looks like it’s all head, seriously. But it tends to weigh over half a ton.

Giant Pacific Octopus

It’s not quite the monster version that the movies depict, but it is huge. Around 600 lbs. and 32 feet of fluid wonder, these creatures tend to live for a while.

Basking Shark

Sharks are already seen as intimidating among ocean-dwelling animals, right? Well, when the basking shark opens its mouth fully and starts to feed, it’s a terrifying sight. But thankfully they feed on plankton and other small matter.

Portuguese Man of War

A lot of jellyfish have insanely long tentacles. But this species can range from 8 to up to 165 feet.

Giant Sea Star

Usually found in the rocky portions of low tide zones, these creatures are roughly two feet in size. They feed on mollusks and smaller organisms though, so you’re not in any danger.