The calculated distance (air line) between Sumqayıt and Türkmenbaşy is approximately 178 miles respectively 286 kilometers.
By car or train, the actual journey to Türkmenbaşy is certainly longer, as only the direct route (as the crow flies) between Sumqayıt and Türkmenbaşy has been calculated here.
Air line (approximately)
286 kilometers
154 nautical miles