The sailfish is the ocean animal widely recognized as the fastest fish in the world, reaching about 110 km/h in short bursts.
Its speed comes from a streamlined body, a rigid bill, powerful muscles, and a deeply forked tail. Sailfish can fold their large dorsal fin, called a sail, into a groove along the back while swimming rapidly. The fin is more often raised when the fish is displaying, maneuvering, or herding prey.
Sailfish live in warm and temperate oceans worldwide. They hunt schooling fish and squid, sometimes working together to push prey into tight groups before striking with their bills. Their bill is not a sword for stabbing; it helps them slash or stun prey.
Speed estimates vary because measuring a wild fish is difficult. The sailfish’s famous record is therefore best understood as a short-burst estimate, not a cruising speed maintained for hours.