The calculated distance (air line) between Sarpang and Samdrup Jongkhar is approximately 76 miles respectively 123 kilometers.
By car or train, the actual journey to Samdrup Jongkhar is certainly longer, as only the direct route (as the crow flies) between Sarpang and Samdrup Jongkhar has been calculated here.
Air line (approximately)
123 kilometers
66 nautical miles