The calculated distance (air line) between Rielasingen-Worblingen and Karlsruhe is approximately 90 miles respectively 145 kilometers.
By car or train, the actual journey to Karlsruhe is certainly longer, as only the direct route (as the crow flies) between Rielasingen-Worblingen and Karlsruhe has been calculated here.
Air line (approximately)
145 kilometers
78 nautical miles