Look at a swordfish. It has a long, flat bill that looks like a sword. The bill is shaped like a flattened oval. The fish is also called a broadbill. A swordfish's bill is long and flat, and it is the part of the fish that looks like a sword.

Other fish have bills too, and the group is called billfishes. But a swordfish's bill is longer than the bills of the other ones. So what is a swordfish's bill for? Scientists think a swordfish uses its sword when it hunts for food. Let us look at the clue.

Squid and cuttlefish eaten by swordfish often have slash marks on their bodies. A slash is a quick cut. The marks are why scientists think a swordfish slashes at prey with its sword. We say they think this, and not that they know, because the marks are a clue.

A grown swordfish has no teeth. It has no scales, either, and it has no pelvic fins. These are parts that a grown swordfish lacks. Think of the fish again: a big fish with a long, flat bill, and with no teeth, no scales and no pelvic fins.

How big does a swordfish get? Female swordfish are larger than male swordfish. As of November 2026, the largest published weight for a swordfish is 650 kilograms, about 1,400 pounds. As of November 2026, a swordfish can grow to about 177 inches long, almost 15 feet, from the tip of its bill to the end of its tail.

Swordfish live in oceans around the world. A swordfish eats fish and squid. In the day, a swordfish stays deep in the ocean, and at night it swims up near the top of the sea to feed. That is its life in the sea.

Words to know

• broadbill: swordfish name
• cuttlefish: squid cousin
• slash: cut quickly