The calculated distance (air line) between Conflans-Sainte-Honorine and Le Havre is approximately 96 miles respectively 154 kilometers.
By car or train, the actual journey to Le Havre is certainly longer, as only the direct route (as the crow flies) between Conflans-Sainte-Honorine and Le Havre has been calculated here.
Air line (approximately)
154 kilometers
83 nautical miles