A nuclear magnetic resonance (NMR)-based method was developed to quickly and accurately determine porosities and densities of tight reservoir rocks from drill cuttings. The method combines low-field NMR and two mass measurements, one in the air and one in a fluid, to determine rock porosity, grain density, and bulk density. The method provides an inexpensive approach to deliver continuous data for evaluation of a drilled well and is especially useful for unconventional reservoirs for evaluating both vertical and horizontal sections of a well.