The calculated distance (air line) between Tain-l'Hermitage and Grenoble is approximately 43 miles respectively 69 kilometers.
By car or train, the actual journey to Grenoble is certainly longer, as only the direct route (as the crow flies) between Tain-l'Hermitage and Grenoble has been calculated here.
Air line (approximately)
69 kilometers
37 nautical miles