As of November 2026, the dwarf lanternshark is grown up at under 8 inches, and the deep-water pygmy shark is about 8 inches long. Also as of November 2026, a great white shark can grow to about 20 feet. Try the arithmetic: 20 feet is 240 inches, and 240 divided by 8 is 30, so a great white is about 30 times as long as an 8-inch shark.

The whale shark is bigger still. As of November 2026 it is the biggest fish in the sea, and whale sharks are usually about 18 to 32 feet long. It swims with its mouth open and filters tiny food out of the water, and its teeth are tiny and play little part in feeding. Set that beside the small sharks. A whale shark of 18 feet, at the short end of the usual range, is 216 inches long, and 216 divided by 8 is 27, so it is about 27 times as long as an 8-inch shark. A whale shark of 32 feet, at the long end of the usual range, is 384 inches long, and 384 divided by 8 is 48, so it is about 48 times as long. And a 32-foot whale shark is 12 feet longer than a 20-foot great white.

As of November 2026 there are more than 500 kinds of sharks, and they start small. A baby white shark is about 4 feet long when it is born. That is 48 inches, and 48 divided by 8 is 6, so a newborn white shark is about 6 times as long as an 8-inch shark.

Teeth give another way to count. A shark loses teeth all its life and grows new ones to replace them. Sharks can shed thousands of teeth in a lifetime. Some species can go through about 30,000 teeth in a lifetime, and some may shed 50,000.

Sharks are very old, and their age is counted in millions of years. As of November 2026, sharks have lived in the sea for more than 400 million years, long before the first trees about 385 million years ago. Subtract 385 from 400 and you get 15, so sharks swam for at least 15 million years before the first trees came along.

Some numbers are about people. Worldwide there are about 70 unprovoked shark bites on people in a typical year, as of November 2026. From 2004 to 2013 the number of people bitten ranged from 53 to 81 a year, a very small number next to the millions of people who go in the sea.

In 2025 the International Shark Attack File confirmed 65 unprovoked shark bites on people worldwide, as of November 2026. Of the hundreds of kinds of sharks, three account for most of them: the white, tiger and bull sharks.

The Greenland shark is a large, slow swimmer that may live for centuries. As of November 2026, one study put the age of a large female at about 392 years, give or take 120. That puts her somewhere between about 272 and about 512 years old.

Words to know

• unprovoked: not started
• dwarf: very small
• centuries: hundreds of years
• shed: lose and drop