The calculated distance (air line) between Kokhav Ya‘aqov and Nablus is approximately 24 miles respectively 38 kilometers.
By car or train, the actual journey to Nablus is certainly longer, as only the direct route (as the crow flies) between Kokhav Ya‘aqov and Nablus has been calculated here.
Air line (approximately)
38 kilometers
20 nautical miles