The calculated distance (air line) between Orsay and Paris 20 Ménilmontant is approximately 15 miles respectively 24 kilometers.
By car or train, the actual journey to Paris 20 Ménilmontant is certainly longer, as only the direct route (as the crow flies) between Orsay and Paris 20 Ménilmontant has been calculated here.
Air line (approximately)
24 kilometers
13 nautical miles