Geohash Encoder / Decoder
Encode a latitude/longitude pair to a geohash — a compact string that groups nearby locations by shared prefix — or decode a geohash back to its centre and bounding box. The encoder interleaves the bits of longitude and latitude (longitude first), five bits per base32 character, using the standard geohash alphabet that omits a, i, l, and o to avoid confusion with digits. Decoding returns the cell's bounding box and its centre point; each extra character shrinks the cell by roughly a factor of two in one dimension. Everything runs locally in your browser.
A geohash interleaves longitude and latitude bits (longitude first) and packs five bits per base32 character using the alphabet 0123456789bcdefghjkmnpqrstuvwxyz. The encoder bisects the longitude range [−180, 180] and latitude range [−90, 90] for each bit; decoding reverses this and returns the cell's bounding box and centre. Longer hashes are more precise — each character roughly halves one dimension's cell width. Cells sharing a prefix are neighbours. Runs locally.