The calculated distance (air line) between Ramat HaSharon and Modiin Ilit is approximately 19 miles respectively 31 kilometers.
By car or train, the actual journey to Modiin Ilit is certainly longer, as only the direct route (as the crow flies) between Ramat HaSharon and Modiin Ilit has been calculated here.
Air line (approximately)
31 kilometers
17 nautical miles