A geohash based cover for a geometry whose uncertainty is described as a circle with center point and a radius is disclosed. In one example, a geohash cover is computed that does not require any expensive geodesic calculations, providing roughly an order of magnitude improvement in speed up of cover calculation. In another example, distance computations are exact compared to a conventional process. In another example, the geohashes returned by the technique can vary between 4 to 9—with a median 6 (a certain conventional process would always return 9 hashes (all the 8 neighbors and the self geohash)). In another example, results are accurate, while still avoiding expensive geodesic computations.