The calculated distance (air line) between Thap Khlo and Nakhon Sawan is approximately 44 miles respectively 71 kilometers.
By car or train, the actual journey to Nakhon Sawan is certainly longer, as only the direct route (as the crow flies) between Thap Khlo and Nakhon Sawan has been calculated here.
Air line (approximately)
71 kilometers
38 nautical miles