The calculated distance (air line) between Utsunomiya and Nishi-Tokyo-shi is approximately 61 miles respectively 99 kilometers.
By car or train, the actual journey to Nishi-Tokyo-shi is certainly longer, as only the direct route (as the crow flies) between Utsunomiya and Nishi-Tokyo-shi has been calculated here.
Air line (approximately)
99 kilometers
53 nautical miles