Who is the biggest of all? As of November 2026, it is the blue whale. It is the biggest animal that has ever lived. A blue whale can weigh 150 to 200 tons. That is many times more than an elephant. A blue whale also lives a long time, about 80 to 90 years.

Elephants are the heaviest animals on land. That is true as of November 2026. There is no heavier animal on land today. A big male African elephant can weigh about 6 tons. The biggest ones weigh about 7 tons. An elephant eats about 165 to 330 pounds of plants a day.

The sperm whale is the biggest of the toothed whales, as of November 2026. It also has the biggest brain of any animal known. It dives deep to hunt squid. Dives routinely reach 2,000 feet and can last 45 minutes. Giant squid have the largest eyes of any living animal, except perhaps the colossal squid. Each eye is about 10 to 11 inches across.

Some reptiles are giants too. The saltwater crocodile is the largest living reptile, as of November 2026. Big males reach 17 to 20 feet or more in length. The Komodo dragon is the largest living lizard. It can grow to about 10 feet long. The green anaconda is the heaviest snake. Big ones weigh hundreds of pounds.

The whale shark is the biggest fish in the sea, as of November 2026. It is a shark, which is a fish. It is not a whale. It eats very small food, mostly plankton and small fish. It filters the food out of the water. The ocean sunfish, or mola, is one of the heaviest bony fish in the world.

The ostrich is the biggest bird in the world, as of November 2026. It cannot fly. A stride can be 10 to 16 feet long. Ostriches lay the biggest eggs of any living land animal. One egg weighs about 3 pounds. The wandering albatross has the longest wings of any living bird. They spread 11 to 12 feet from tip to tip.

Big does not always mean animal. As of November 2026, the General Sherman Tree, a giant sequoia in California, is the biggest tree in the world by the amount of wood in it. It is a tree, not an animal.

Words to know

• toothed: with teeth
• colossal: huge
• sequoia: giant tree
• plankton: tiny sea life

The short version

As of November 2026, the biggest animal that has ever lived is the blue whale. It can be about 100 feet long and can weigh 150 to 200 tons, many times more than an elephant, the biggest land animal. It is bigger than any dinosaur known.

Quick facts

• A blue whale can be about 100 feet long and weigh 150 to 200 tons.
• As of November 2026, elephants are the heaviest living land animals.
• A blue whale lives about 80 to 90 years.
• As of November 2026, the whale shark is the biggest fish. It is a fish, not a whale.
• As of November 2026, the saltwater crocodile is the largest living reptile.