The calculated distance (air line) between Bīr Zayt and Khān Yūnis is approximately 68 miles respectively 109 kilometers.
By car or train, the actual journey to Khān Yūnis is certainly longer, as only the direct route (as the crow flies) between Bīr Zayt and Khān Yūnis has been calculated here.
Air line (approximately)
109 kilometers
59 nautical miles