The calculated distance (air line) between Kosum Phisai and Udon Thani is approximately 83 miles respectively 133 kilometers.
By car or train, the actual journey to Udon Thani is certainly longer, as only the direct route (as the crow flies) between Kosum Phisai and Udon Thani has been calculated here.
Air line (approximately)
133 kilometers
72 nautical miles