What is the largest animal on Earth?
Quick answer
The blue whale is the largest animal living on Earth, and the largest known to have ever lived. Adults can reach about 30 m (98 ft) long and weigh around 150 tonnes or more, heavier than any known dinosaur. Despite its size, it feeds almost entirely on tiny shrimp-like animals called krill.
Key facts
- Length
- Up to about 30 m (98 ft)
- Weight
- Usually 100–150 tonnes; some estimated near 190 tonnes
- Diet
- Krill
- Status
- Endangered (IUCN)
Size comparisons
| Body part | Size |
|---|---|
| Heart | About the size of a small car, around 180 kg |
| Tongue | Can weigh as much as an elephant |
| Blood vessels | Main artery wide enough for a small child to crawl through |
| Calf at birth | About 7 m long, around 2.5 tonnes |
| Calf growth | Gains roughly 90 kg a day on milk |
Is it bigger than dinosaurs?
The largest dinosaurs, long-necked sauropods like Argentinosaurus, may have reached similar lengths, but are estimated to have weighed less, perhaps 70–100 tonnes. Water supports a whale’s weight, allowing it to grow heavier than any land animal could.
Feeding: giant gulps
Blue whales are filter feeders. A whale lunges into a swarm of krill and takes in a mouthful of water larger than its own body, then pushes the water out through comb-like baleen plates, trapping the krill. During the feeding season, a blue whale may eat several tonnes of krill a day.
The loudest animal
Blue whale calls can reach about 188 decibels, louder than a jet engine, and travel hundreds of kilometers underwater. They’re so low-pitched that humans can barely hear them.
Back from the brink
Commercial whaling killed hundreds of thousands of blue whales in the 20th century. Hunting was banned worldwide in 1966. Populations are slowly recovering, but the species is still listed as endangered.
Other record giants
- Largest fish: the whale shark; see what the largest shark is
- Largest land animal: the African bush elephant
- Longest-lived animals: see which animal has the longest lifespan
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