The calculated distance (air line) between Naberezhnyye Chelny and Zainsk is approximately 31 miles respectively 50 kilometers.
By car or train, the actual journey to Zainsk is certainly longer, as only the direct route (as the crow flies) between Naberezhnyye Chelny and Zainsk has been calculated here.
Air line (approximately)
50 kilometers
27 nautical miles