The calculated distance (air line) between Sarlat-la-Canéda and Montpellier is approximately 159 miles respectively 255 kilometers.
By car or train, the actual journey to Montpellier is certainly longer, as only the direct route (as the crow flies) between Sarlat-la-Canéda and Montpellier has been calculated here.
Air line (approximately)
255 kilometers
138 nautical miles