The calculated distance (air line) between Si Racha and Nakhon Ratchasima is approximately 147 miles respectively 236 kilometers.
By car or train, the actual journey to Nakhon Ratchasima is certainly longer, as only the direct route (as the crow flies) between Si Racha and Nakhon Ratchasima has been calculated here.
Air line (approximately)
236 kilometers
128 nautical miles