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Differences: Dolphins to Porpoise


The differences between dolphins and porpoises are not at first obvious, but the two species are not difficult to distinguish between once you know the key points of difference.

Feature Dolphin Characteristic Difference in a Porpoise
The nose

Dolphin diifference to porpoise - snoutA dolphin usually has a pointed snout


Porpoise difference to dolphin - snoutA porpoise snout is short and blunt like a cartoon fish sketch
(never strongly pointed)

The fin

(Some species of both have no fin on their back)

Dolphin fin differenceThe leading edge of the fin on a dolphin's back is shaped like a curling wave
(Called the dorsal fin)

The lPorpoise fin differenceeading edge of a porpoise's back fin is straight.

The porpoise's fin is also triangular like a shark's

The teeth

(The difference in teeth between dolphins and porpoises reflects the difference in the fish that they catch)

Dolphin teeth differenceDolphins have pointed cone-shaped teeth


Porpoise teeth differencePorpoise teeth are flat, spade shaped, with upper edges that are long and sharp
Size Dolphins grow up to 12 feet long Porpoises are usually less than 7 feet long
Shape Dophin shape differenceDolphins are longer and sleeker in shape Porpoise shape differencePorpoises are shorter and more compact
Sounds Dolphins produce sounds we can hear (and are talkative!) Porpoise sounds are inaudible to us
Behaviour Dolphins have much less fear of humans - will ride the waves alongside boats Porpoises are shy - you are much less likely to see one - wild or captive.
Rarely seen at surface unless up to breathe.
Groups Dolphins live in large groups Porpoises live in pods of 2 - 4
Lifespan Dolphins can live for more than 50 years Porpoises do not live long past the age of 15


Dolphins and porpoises are both mammals, this means that they have major differences to fish.

As mammals both dolphins and porpoises have lungs and they breathe air through their blowholes, but although they have no gills they can still dive for up to 20 minutes.

Another characteristic as mammals is that dolphins and porpoises give birth to live young which they nurse, and which are born with hair!


Dolphins reputedly spend one third of their day sleeping, one third eating and one third playing or making love.

I wrote this page because I recently found myself rescuing a stranded dolphin


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