The calculated distance (air line) between Hallein and Klagenfurt am Wörthersee is approximately 93 miles respectively 149 kilometers.
By car or train, the actual journey to Klagenfurt am Wörthersee is certainly longer, as only the direct route (as the crow flies) between Hallein and Klagenfurt am Wörthersee has been calculated here.
Air line (approximately)
149 kilometers
80 nautical miles