The calculated distance (air line) between Saint-Quentin-en-Yvelines and Le Chesnay is approximately 6 miles respectively 9 kilometers.
By car or train, the actual journey to Le Chesnay is certainly longer, as only the direct route (as the crow flies) between Saint-Quentin-en-Yvelines and Le Chesnay has been calculated here.
Air line (approximately)
9 kilometers
5 nautical miles