The calculated distance (air line) between Mouans-Sartoux and Montpellier is approximately 155 miles respectively 249 kilometers.
By car or train, the actual journey to Montpellier is certainly longer, as only the direct route (as the crow flies) between Mouans-Sartoux and Montpellier has been calculated here.
Air line (approximately)
249 kilometers
134 nautical miles