Which extinct giant shark is the largest predatory fish?

Megalodon was the largest predatory fish known from the fossil record.

Megalodon, scientifically named Otodus megalodon, was an extinct giant mackerel shark that lived from approximately 23 to 3.58 million years ago, spanning the Miocene and early Pliocene epochs. It was a powerful marine predator that likely hunted large marine mammals, including whales.

Because sharks have cartilage rather than fully mineralized skeletons, megalodon is known mainly from teeth and occasional vertebrae. Its teeth could exceed 180 millimeters in slant height, and their triangular, serrated form reveals its relationship to other large predatory sharks. Scientists estimate its size from these fossils and comparisons with living lamniform sharks, so exact maximum length remains debated.

Megalodon is often confused with the modern great white shark, but it was not its direct ancestor and is classified in the extinct family Otodontidae. The whale shark is larger than any living predatory shark in some measurements, but it is a filter feeder, not a predator.