The calculated distance (air line) between Cosne-Cours-sur-Loire and Saint-Étienne is approximately 153 miles respectively 247 kilometers.
By car or train, the actual journey to Saint-Étienne is certainly longer, as only the direct route (as the crow flies) between Cosne-Cours-sur-Loire and Saint-Étienne has been calculated here.
Air line (approximately)
247 kilometers
133 nautical miles