3D cell culturing by Magnetic Levitation Method (MLM) is the application of growing 3D tissue by inducing cells treated with magnetic nanoparticle assemblies in spatially varying magnetic fields, using neodymium magnetic drivers and promoting cell-to-cell interactions by levitating the cells up to the air/liquid interface of a standard petri dish. The magnetic nanoparticle assemblies consist of magnetic iron oxide nanoparticles, gold nanoparticles, and the polymer polylysine. 3D cell culturing is scalable, with the capability of culturing as few as 500 cells up to millions of cells, or from a single dish to high-throughput low volume systems. Once magnetized cultures are generated, they can also be used as the building block material, or the "ink" for the magnetic 3D bioprinting process.