The calculated distance (air line) between Dayr Ḩāfir and Aleppo is approximately 31 miles respectively 49 kilometers.
By car or train, the actual journey to Aleppo is certainly longer, as only the direct route (as the crow flies) between Dayr Ḩāfir and Aleppo has been calculated here.
Air line (approximately)
49 kilometers
27 nautical miles