The calculated distance (air line) between Nakhon Thai and Nakhon Sawan is approximately 107 miles respectively 172 kilometers.
By car or train, the actual journey to Nakhon Sawan is certainly longer, as only the direct route (as the crow flies) between Nakhon Thai and Nakhon Sawan has been calculated here.
Air line (approximately)
172 kilometers
93 nautical miles