The calculated distance (air line) between Mazār-e Sharīf and Dŭstí is approximately 96 miles respectively 155 kilometers.
By car or train, the actual journey to Dŭstí is certainly longer, as only the direct route (as the crow flies) between Mazār-e Sharīf and Dŭstí has been calculated here.
Air line (approximately)
155 kilometers
84 nautical miles