Magnetic skyrmions are going to be the prospective candidate for next generation ultra-high density data storage due to their tunable dimension down to few nm and requirement of low current density for their motion. This paper presents the stabilization of skyrmion and various ways of scaling skyrmion dimension in magnetic nanostructure with perpendicular magnetic anisotropy. The micromagnetic energetics of the system has been explained as an additive contribution due to the Heisenberg exchange, Dzyaloshinskii-Moriya interaction, anisotropy and Zeeman field. Emphasis has been provided towards the understanding of the complex interplay between the energy parameters in response to the modification of asymmetric exchange, anisotropy and their effect in magnetization reversal for circular nano-disks of different dimensions. Fine tuning of skyrmion diameter is shown with the presence of magnetic defect in the nanostructure. Stabilization of single skyrmion and symmetric multi skyrmion lattice from a ferromagnetic multi domain state has been explained for the nanostructures in the light of subtle balance of the energies, arising due to the Dzyaloshinskii-Moriya interaction and out-of-plane magnetic field. © 2018 Elsevier B.V.