We used x-ray nanotomography to characterize the three-dimensional ͑3D͒ morphology and topology of dealloyed nanoporous gold after coarsening. The interface shape distribution obtained from the nanotomography measurement shows that the coarsening does not proceed by bulk diffusion. The surface normal distribution shows that the morphology of the nanoporous gold is anisotropic. The topology of nanoporous gold is similar to that of other bicontinuous structures created by phase separation, despite the radically different method used to produce the structures. This work opens the door to time-resolved, in situ studies of coarsening of nanoporous gold in 3D.