The calculated distance (air line) between Nakhon Phanom and Kut Chap is approximately 146 miles respectively 235 kilometers.
By car or train, the actual journey to Kut Chap is certainly longer, as only the direct route (as the crow flies) between Nakhon Phanom and Kut Chap has been calculated here.
Air line (approximately)
235 kilometers
127 nautical miles