I have points with a given latlong and a distance around them - e.g. { 40.6826048,-74.0288632 : 20 miles, 51.5007825,-0.1258957 : 100 miles}. If I pick a fixed geohash lengt
Have a look at this -> ProximityHash.
ProximityHash generates a set of geohashes that cover a circular area, given the center coordinates and the radius. It also has an additional option to use GeoRaptor that creates the best combination of geohashes across various levels to represent the circle, starting from the highest level and iterating till the optimal blend is brewed. Result accuracy remains the same as that of the starting geohash level, but data size reduces considerably, thereby improving speed and performance.