Therefore the volume of a singularity must be zero. The event horizon that surrounds a singularity, however, will have a size that depends on the mass of the black hole. A singularity cannot and has not existed, in our universe, therefore it has no size. Theoretically a singularity has no dimensions, so it cannot have a size. If not, then the mass of the black hole would be infinite. NASA / … According to GR, the size of the singularity is zero. If it had a size of any kind it must have at least two, no three dimensions.
A singularity is a point in space-time in which matter and energy are infinitely dense, as at the center of a black hole or at the moment of the Big Bang. That is basically the definition of the word "singularity." People are working on extending GR to include quantum mechanics, but we don't yet have a theory of quantum gravity. A singularity in cosmology refers to a place where the density is infinite. At present, the accepted value of this limit is believed to be 1.39 Solar Masses (i.e. The hot Big Bang was preceded by a state of cosmic inflation, but the idea that all of it must be preceded by a singularity is woefully out of date. It truly has no size, and all of the singularity's mass is contained at that one point. Otherwise we would not be able to measure the size.