The calculated distance (air line) between Mechelen-aan-de-Maas and Jette is approximately 59 miles respectively 96 kilometers.
By car or train, the actual journey to Jette is certainly longer, as only the direct route (as the crow flies) between Mechelen-aan-de-Maas and Jette has been calculated here.
Air line (approximately)
96 kilometers
52 nautical miles