The calculated distance (air line) between Ko Pha Ngan and Surat Thani is approximately 64 miles respectively 103 kilometers.
By car or train, the actual journey to Surat Thani is certainly longer, as only the direct route (as the crow flies) between Ko Pha Ngan and Surat Thani has been calculated here.
Air line (approximately)
103 kilometers
55 nautical miles