Overall, this work establishes nascent processing guidelines to produce freestanding, millimeter thick optically transparent MAPbX3 ceramics. It also provides the building blocks needed to eventually produce higher density (>0.9999) perovskite ceramics with maximized optical transparency. While the focus here has been on MAPbBr3 and MAPbCl3, this methodology should be applicable to other room temperature, cubic phase lead halide perovskites (e.g., FAPbBr3, FAPbCl3, FA/CsPbX3, FA/MA/CsPbX3, etc.). However, this will require meticulous control and understanding of the processing methods from initial powder production to all stages of sintering/densification. Establishing this knowledge will permit the rapid production of ready-to-use halide perovskite ceramics with microstructures, optoelectronic properties, and physical dimensions that meet the performance metrics of specific applications. ASSOCIATED CONTENT Materials; /2 XRD methods; TGA methods; crystal growth methods; ball-milling details; uniaxial pressing details; SEM methods; optical profilometry methods; optical imaging methods; transmission measurement methods and simulations; Archimedes density measurement methods; X-Ray nanotomography methods; pore modelling details, table of MAPbX3 ceramics properties; transmission spectra of MAPbX3 ceramics, single crystals, and simulations from 300 to 3000 nm; /2XRD patterns of MAPbX3 powders, single crystals, ceramics, and simulations; theromgravimetric analysis data; SEM images of MAPbX3 powders; images of MAPbX3 green body ceramics; images of all MAPbBr3 and MAPbCl3 ceramics; images of MAPbX3 single crystals; transmission spectra of all MAPbX3 ceramics; ceramic transmission spectra from 0.3 to 25 m; SEM sizing histograms for each ceramic; optical profilometry surface roughness maps of MAPbX3 ceramics and corresponding polished stainless steel spacers, NanoCT data video and further SEM/tomography images of analyzed area, min and max Feret pore size histograms, scattering efficiencies, scattering cross-sections, and extinction coefficients from pore modelling, transmission spectra from pore modelling, contour plots from modeling, comparison of polydisperse and monodisperse transmission spectra, experimental transmission spectra vs. press time figure and.