The calculated distance (air line) between Saint-Josse-ten-Noode and Mechelen is approximately 13 miles respectively 20 kilometers.
By car or train, the actual journey to Mechelen is certainly longer, as only the direct route (as the crow flies) between Saint-Josse-ten-Noode and Mechelen has been calculated here.
Air line (approximately)
20 kilometers
11 nautical miles