ProPan is a comprehensive prokaryotic pan-genome database toward understanding genomic dynamics. It covered 1,504 species across archaea and bacteria (including 51,882 strain genomes), by which, multiple analyses were processed: species orthologous gene clustering and pan-genome profile, gene cluster nucleotide diversity calculation, species metabolism circle, multiple function annotation and etc. Taken together, ProPan is devoted to accelerate various prokaryotic species research via post-processed dataset storing, multiple-dimensional analyses, and instant visualizations from pan-genomics.