Data sets used to prepare Figures 5-14 in the Journal of Chemical Physics article entitled "Structure of alkali magnesium, zinc, and calcium metasilicate glasses." The data sets describe the structure of the metasilicate composition glasses (A2O)_x(XO)_{0.50-x}(SiO2)_{0.50}, with A = Na or K, X = Mg, Zn or Ca, and x = 0.25 or 0.33, as measured using neutron and high-energy x-ray diffraction and 25Mg solid-state nuclear magnetic resonance spectroscopy.