The calculated distance (air line) between Bayt Fajjār and Khān Yūnis is approximately 54 miles respectively 86 kilometers.
By car or train, the actual journey to Khān Yūnis is certainly longer, as only the direct route (as the crow flies) between Bayt Fajjār and Khān Yūnis has been calculated here.
Air line (approximately)
86 kilometers
47 nautical miles