The calculated distance (air line) between Suwannaphum and Udon Thani is approximately 142 miles respectively 229 kilometers.
By car or train, the actual journey to Udon Thani is certainly longer, as only the direct route (as the crow flies) between Suwannaphum and Udon Thani has been calculated here.
Air line (approximately)
229 kilometers
123 nautical miles