The calculated distance (air line) between Dayr Dibwān and Khān Yūnis is approximately 69 miles respectively 111 kilometers.
By car or train, the actual journey to Khān Yūnis is certainly longer, as only the direct route (as the crow flies) between Dayr Dibwān and Khān Yūnis has been calculated here.
Air line (approximately)
111 kilometers
60 nautical miles