What Is the Difference Between Blowfish & Puffer Fish?

By Whitney Lowell

When looking into fish and creatures to add to your home aquarium or just learning about aquatic creatures, you may come across blowfish and puffer fish and wonder what's the difference. Well, these two creatures are actually one and the same.

The Tetraodontidae Family

Blowfish and puffer are both common names for the Tetraodontidae family of fish, which includes 196 or so species. Most puffer fish inhabit saltwater environments, but some species inhabit brackish and freshwater. The Tetraodontidae family is grouped by fish species that have the ability to inflate their bodies by quickly ingesting water. Biologists believe that this ability was developed because puffer fish are clumsy and slow swimmers, making them vulnerable to predators. Puffer fish cannot quickly escape predators, but by inflating themselves, they can quickly become much larger than some predators can eat, and their blowing-up action may scare some away.


Only some species of puffer fish are covered in spines on their skin, but almost all puffer fish contain tetradotoxin, a substance that makes the fish foul-tasting to predators and extremely poisonous to humans. Tetradotoxin is up to 1,200 times more poisonous than cyanide -- and each fish contains enough toxin to kill about 30 adults.

A Dangerous Delicacy

Despite the potential risk of death, puffer fish are considered a delicacy -- an expensive one. In Japan, fugu is prepared and served only by trained and licensed chefs, because one bad cut that releases the toxin into the meat can be fatal.