The calculated distance (air line) between Cergy-Pontoise and Ivry-sur-Seine is approximately 21 miles respectively 33 kilometers.
By car or train, the actual journey to Ivry-sur-Seine is certainly longer, as only the direct route (as the crow flies) between Cergy-Pontoise and Ivry-sur-Seine has been calculated here.
Air line (approximately)
33 kilometers
18 nautical miles