How fast can an Alligator run!? There’s a lot of conjecture about this, so let me start by saying Crocodilians are NOT built for land speed. Crocodilians are long animals with short legs and a low centre of gravity. The larger species are also very bulky and heavy. The Australian Freshwater Crocodile is the fastest crocodilian on land, with a top running speed of around 16km an hour (10mph) over short distances. This is based on documented, observed, repeatable sprint performance in open habitat