A5

A5 is a Discrete Global Grid System (DGGS) that turns any location, line, or polygon on the globe into a pentagonal cell or a collection of cells. Each cell is stored as a compact 64-bit integer, giving a single, permanent identifier for a piece of the planet. The project began as a visualization experiment and has since grown into a practical geospatial indexing platform.

The v1.0 release finalizes the grid and index definitions and adds coverings with set operations, spatial hierarchy functions, and faster indexing. Libraries and tools in multiple languages build on the same cell model, so identifiers stay consistent across systems. A public example is the FIRMS Explorer, which uses A5 to aggregate 631 million fire detections worldwide since 2000.

It is aimed at geospatial developers, data engineers, and analytics teams who need a stable global grid for indexing, aggregation, and spatial queries at scale. Because cells are integers, they work well in databases and distributed pipelines where compact keys and deterministic hierarchy matter more than familiar map tiles.

New users should start with the About and Examples pages to understand the pentagonal cell model, then try the available language libraries on a small dataset before migrating production pipelines. Expect to build your own visualization layer, since A5 focuses on the grid and indexing rather than end-user maps. Overall, it is a well-defined foundation for global spatial data work.