The calculated distance (air line) between Sevenoaks and Stoke-on-Trent is approximately 156 miles respectively 252 kilometers.
By car or train, the actual journey to Stoke-on-Trent is certainly longer, as only the direct route (as the crow flies) between Sevenoaks and Stoke-on-Trent has been calculated here.
Air line (approximately)
252 kilometers
136 nautical miles