The calculated distance (air line) between Kelsterbach and Schwalbach am Taunus is approximately 6 miles respectively 10 kilometers.
By car or train, the actual journey to Schwalbach am Taunus is certainly longer, as only the direct route (as the crow flies) between Kelsterbach and Schwalbach am Taunus has been calculated here.
Air line (approximately)
10 kilometers
5 nautical miles