The calculated distance (air line) between Międzyrzec Podlaski and Częstochowa is approximately 178 miles respectively 286 kilometers.
By car or train, the actual journey to Częstochowa is certainly longer, as only the direct route (as the crow flies) between Międzyrzec Podlaski and Częstochowa has been calculated here.
Air line (approximately)
286 kilometers
154 nautical miles