A5 - Global, equal-area, millimeter-accurate geospatial index Website: A5Geo.org Introduction A5 is a geospatial index that partitions the world into pentagonal cells. The cells are available at 32 different resolution levels, with the largest cell covering the whole world, and the smallest less than 30mm². Within each resolution level the cells have equal area, to within 2%. A5 cells provide simple way to represent spatial data as a collection of cells, which together represent regions on the g...