Blue whale Facts for Kids

Balaenoptera musculus · bay-leen-OP-ter-uh MUS-kyoo-lus

The biggest animal that has ever lived, bigger than any dinosaur.

🏃 20 mph32 km/h1
⚖️ 165 tons150 tonnes1
📏 110 ft34 m1 long
🎂 80 to 90 years80 to 90 years1
🍽️ tiny sea life
In danger (Endangered)

The blue whale is the biggest animal ever. It is bigger than any dinosaur. It eats tiny shrimp-like animals called krill.

Blue whales have no teeth. Instead they have baleen, rows of bristly plates that work like a sieve: the whale gulps a huge mouthful of sea water and krill, pushes the water out, and keeps the krill. It breathes air through two blowholes on top of its head.

Even though it is the largest animal on Earth, the blue whale eats some of the smallest: krill. In the feeding season it eats an enormous amount, then lives off its stored fat on long journeys. Blue whales call to each other with deep, loud sounds that travel a long way through the ocean. Whaling once made them very rare; since it stopped, they have slowly started to come back.

How big is a blue whale?

🧒 our measuring child, 4 ft1.2 m🐋 Blue whale, 110 ft33.5 m long

Blue whale in numbers

Length	110 ft34 m1maximum, Antarctic blue whales
Height at the shoulder	no checked number yet
Weight	165 tons150 tonnes1
Top speed (swimming)	20 mph32 km/h1
How long it lives	80 to 90 years80 to 90 years1in the wild, estimated average
What it eats	krill, tiny shrimp-like animals, by the mouthful
Where it lives	every ocean
What kind	Mammals
Is it in danger?	In danger (Endangered)2

A number we couldn’t find on a page we trust says so, instead of guessing.

Wow!

The blue whale is bigger than any dinosaur that ever lived.
It has no teeth: it eats with baleen, like a giant sieve.
Its calls are among the loudest sounds any animal makes.

Compare the blue whale

Friends and neighbours

Three questions

What does the blue whale eat?

Tiny sea lifeMeatFish

The answer: Tiny sea life. It eats krill, tiny shrimp-like animals, by the mouthful.

Where does the blue whale live?

DesertOceanForest

The answer: Ocean. It lives in every ocean.

Which is longer, the blue whale or the cheetah?

The blue whaleThe cheetahThey're the same

The answer: The blue whale. Look at them side by side on the compare stage.

Books about the blue whale, free at the library

Ask a grown-up to tap the button: it shows where to borrow a book about the blue whale for free.

Where these numbers come from

NOAA Fisheries, checked 30 October 2026.
Wikidata, from the IUCN Red List, checked 30 October 2026.
Wikidata, Blue whale (Q42196), checked 30 October 2026.