Overview: SPHEREx is a NASA Medium Explorer mission designed to 1) constrain the physics of inflation by measuring its imprints on the three-dimensional large-scale distribution of matter, 2) trace the history of galactic light production through a deep multi-band measurement of large-scale clustering, and 3) investigate the abundance and composition of water and biogenic ices in the early phases of star and planetary disk formation. SPHEREx will obtain near-infrared 0.75-5.0 um spectra every 6" over the entire sky. It implements a simple instrument design with a single observing mode to map the entire sky four times during its nominal 25-month mission. SPHEREx will also have strong scientific synergies with other missions and observatories, resulting in a rich legacy archive of spectra that will bear on numerous scientific investigations. SPHEREx is projected to launch towards the end of February 2025.