A dynamic finite-element code was used in its “application mode” to analyze the dynamic fracture responses of a single-edged-notch specimen subjected to fixed end rotation, a wedge-loaded single-edged-notch specimen, and an internally notched semicircular specimen subjected to end rotation and shear deformation. The dynamic fracture responses in each of the three specimens consisting of A533B steel, Homalite-100, or Araldite B photoelastic polymers were nearly identical despite the widely varying material properties. A scaling law for dynamic fracture of specimens with identical geometry and similar dynamic fracture toughness versus crack velocity relation, but with different material, is proposed. The numerical results also show that significant energy dissipation due to viscoelastic damping cannot possibly occur during the short duration of dynamic fracture.