The calculated distance (air line) between Quincy-Voisins and Paris 18 Buttes-Montmartre is approximately 24 miles respectively 39 kilometers.
By car or train, the actual journey to Paris 18 Buttes-Montmartre is certainly longer, as only the direct route (as the crow flies) between Quincy-Voisins and Paris 18 Buttes-Montmartre has been calculated here.
Air line (approximately)
39 kilometers
21 nautical miles