In some examples, a query including signal values providing measures of signals between a first wireless device and corresponding access points is received. Access points are ranked for the query based on sorting the signal values. Similarity values are computed, using the ranking, between the query and respective fingerprints of signal values collected at a plurality of locations in an area, each signal value of the signal values in the fingerprints providing a measure of a signal between at least one wireless device at a location of the plurality of locations and a respective access point of the access points. A location of the first wireless device is determined based on the computed similarity values.