Grid Point Code: Ten Characters to a Doorway

Field notes

The encoding proceeds through ten five-by-five subdivisions, with each character narrowing the geographic cell by a constant factor. The page illustrates the hierarchy using a Toronto point, progressing from a block of the world to country, region, building, entrance, and doorway scales. It also states that encoding and decoding work offline with arithmetic and no lookup table, while the linked specification, documentation, comparison tools, proofs, and Apache 2.0 source provide routes for technical examination.