Although dolphins and porpoises share many similarities—both breath air, are warm-blooded, have intelligence—they are actually quite different. While the difference between dolphin and porpoise is subtle, you can easily tell them apart with some common indicators.
Here are 5 key differences between dolphins and porpoises.
1. Dolphins Are Far More Prevalent Than Porpoises
While 40 dolphin species exist including 5 species of river dolphins, only 7 porpoise species are known to scientists. If you see a marine mammal that looks like a dolphin, chances are it’s a dolphin.
2. Porpoise Noses Are Shorter Than Dolphin Noses
The nose of a dolphin is elongated and almost “beak-like”. On the other hand, porpoise noses are much shorter.
Even though the most familiar species of dolphin is the bottlenose dolphin, most species of dolphins have this longer nose.
3. Their Teeth Are Shaped Differently
While you may never have the opportunity to see dolphin or porpoise teeth up close, it’s worth knowing the difference in shape. While dolphins have cone shaped teeth, porpoise teeth are spade shaped.
4. A Curved Fin Means It’s a Dolphin
The proper name for the fin in the middle of a marine animal’s back is a dorsal fin. Although both porpoises and dolphins have dorsal fins, a dolphin has a hooked or curved dorsal fin while a porpoise’s dorsal fin is triangular. In general, dolphins have a leaner, streamlined body whereas a porpoise is broader.
5. Porpoises Aren’t Social Like Dolphins
Dolphins communicate with each other by emitting whistling sounds through their blowholes. As far as scientists know, porpoises do not communicate in the same way. In fact, scientists don’t think that porpoises communicate via sound at all.

Bonus Fact: Did you know that a killer whale is actually a dolphin? That’s right, the killer whale is the largest member of the oceanic dolphin family.
Have you ever seen a porpoise? Let us know where in the comments below.