These Are the World’s Biggest Fish, Ranked by Size

We all know how huge the ocean is, and that means many of its species swimming below the surface are also incredibly large. Fish come in all shapes and sizes, but the biggest ones are something else. Here are 15 of the biggest fish, ranked by size.

Basking Shark

Now, just so you know, the basking shark is the second biggest fish in the world. These guys look a little scary because of their giant mouths, but they’re harmles, too. They can stretch out to around 30 feet long and mostly cruise around cooler waters like the North Atlantic.

Sawfish

It might look like something from a sci-fi movie, however, the sawfish is very real. These large fish have long, flat snouts lined with sharp teeth, almost like a chainsaw. Sometimes, they grow up to 25 feet, which is seriously huge. They live in both saltwater and freshwater and are often found in warm, shallow areas.

Greenland Shark

If you’re into mysterious animals, the Greenland shark is one to know. At first, it may not look like much, but don’t let their slowness fool you. This species will grow to be about 24 feet long, though they move at a snail’s pace. What makes them really fascinating is how long they live, sometimes up to 400 years.

Pacific Sleeper Shark

To be perfectly honest, this one doesn’t get enough attention. It’s easy to overlook the Pacific sleeper shark because it doesn’t make a big splash, but it’s still enormous. These deep-sea dwellers can reach lengths of up to 23 feet. They’re slow and kind of mysterious, living mostly in dark, cold parts of the Pacific Ocean.

Great White Shark

Seriously, this is a fish that needs no introduction. The great white shark isn’t the biggest fish overall, but it’s definitely one of the most powerful. On a few occasions, they’ve grown up to 20 feet long, and some can weigh over 5,000 pounds. These sharks are built like tanks and can even leap out of the water when hunting seals.

Beluga Sturgeon

As one of the biggest freshwater species, the beluga sturgeon deserves a mention. These fish can reach lengths of 20 feet and live in rivers that flow into the Caspian and Black Seas. What’s unusual is that they’re ancient, as they’ve been around since the time of dinosaurs.

Tiger Shark

Every once in a while, someone spots a tiger shark and just stops in their tracks. These large predators can grow up to 18 feet and weigh around 1,400 pounds.

They’re named for the faint stripes along their bodies, which kind of fade as they age. What’s really wild about them is their appetite, as they’ll eat pretty much anything.

Wels Catfish

This next one is known more in Europe, but it’s worth mentioning because of its size. The wels catfish can grow up to 16 feet long and weigh hundreds of pounds. It’s a bottom-dweller, meaning it hangs out in deep lakes and slow rivers.

Giant Freshwater Stingray

You probably didn’t expect a stingray to show up here, but this species definitely belongs on this list. Found in rivers in Southeast Asia, this creature can weigh over 1,000 pounds and reach lengths of more than 16 feet. They spend most of their time hiding on the muddy bottom of rivers, so they’re rarely seen.

Arapaima

Believe it or not, this next one breathes air. Way out in the rivers of the Amazon, the arapaima swims around like a living dinosaur. These fish can grow up to 15 feet and weigh several hundred pounds.

They’ve got a long, sleek body and breathe air, which means they have to surface often. That’s kind of weird for a fish, but it helps them survive in waters that are low on oxygen.

Mako Shark

Some fish are big, some are fast, and then there’s the mako shark, which is both. These sleek sharks can grow up to 13 feet and reach speeds over 40 miles per hour. If you blink, you might miss one. They stand out for how quick and agile they are, especially compared to other large sharks.

Ocean Sunfish

What you may not know is that the ocean sunfish, also called the mola mola, is one of the heaviest bony fish out there. Some of them weigh over 5,000 pounds, though they’re not very long, usually around 10 feet.

You’ll often find them near the surface, just hanging out and soaking up the sun. They mostly eat jellyfish, which explains their slow, clumsy swimming.

Alligator Gar

It’s crazy to think that the alligator gar is native to the southern United States and can grow over 10 feet long. It’s got a long snout filled with sharp teeth, kind of like its namesake. Most people don’t realize it’s a fish at first because it looks so much like a reptile.