Scientists at a British museum have worked out the weight of Sophie, one of the world's most complete Stegosaurus skeletons.

London's Natural History Museum says Sophie, a young adult when it died, weighed around 1.6 tons and was about the same size as a small rhinoceros.

The scientists worked out the dinosaur's body mass after creating a 3-D digital version of its skeleton, calculating the volume of flesh around the bones, and comparing the data with information from similar-sized modern animals.

The skeleton, which is 85 percent intact, greets visitors entering the museum. It was discovered in 2003 at Red Canyon Ranch in Wyoming.