My son got a fisher price dinosaur playset, and the dino to dino to human scale looked pretty much right on. It looks about 28mm scale, and I am comparing a caveman, velociraptor, and iguanadon (I think) to each other. They also have Trex, Triceratops, and many others.
The website is at http://www.imaginext.com and then go to the dinosaur area.