The calculated distance (air line) between Kota Kinabalu and Lahad Datu is approximately 169 miles respectively 271 kilometers.
By car or train, the actual journey to Lahad Datu is certainly longer, as only the direct route (as the crow flies) between Kota Kinabalu and Lahad Datu has been calculated here.
Air line (approximately)
271 kilometers
146 nautical miles