The calculated distance (air line) between Nakhon Si Thammarat and Chumphon is approximately 152 miles respectively 245 kilometers.
By car or train, the actual journey to Chumphon is certainly longer, as only the direct route (as the crow flies) between Nakhon Si Thammarat and Chumphon has been calculated here.
Air line (approximately)
245 kilometers
132 nautical miles