zPARES parallel eigenvalue solver: z-Pares is a package for solving generalized eigenvalue problems. z-Pares is designed to compute a few eigenvalues and eigenvectors of sparse matrices. The symmetries and definitenesses of the matrices can be exploited suitably. z-Pares implements a complex moment based contour integral eigensolver. z-Pares computes eigenvalues inside a user-specified contour path and corresponding eigenvectors. The most important feature of z-Pares is two-level Message Passing Interface (MPI) distributed parallelism.