The tail club of an Ankylosaurus is usually estimated at around 20 kg , or about 40 lb. For the animal as a whole, sources commonly place Ankylosaurus around 4,500 to 8,000 kg total body weight, depending on the reference.

Quick Scoop

A useful rule of thumb is that the club was heavy enough to be a serious weapon, but still small compared with the dinosaur’s body. Different estimates vary because fossil material is limited and researchers reconstruct soft tissue and bone proportions differently.

Why estimates differ

  • Some discussions cite about 19.9 kg for the club specifically.
  • Museum and reference sources often give Ankylosaurus a body mass in the multi-ton range , which helps put the club in context.
  • The exact weight would have varied by species, individual size, and how much of the tail knob was covered by surrounding tissue.

TL;DR

An Ankylosaurus tail club was probably about 20 kg / 40 lb. That’s the most concrete estimate I found, while the full animal itself was several tons.