The calculated distance (air line) between Guwahati and Samdrup Jongkhar is approximately 45 miles respectively 73 kilometers.
By car or train, the actual journey to Samdrup Jongkhar is certainly longer, as only the direct route (as the crow flies) between Guwahati and Samdrup Jongkhar has been calculated here.
Air line (approximately)
73 kilometers
39 nautical miles