The calculated distance (air line) between Oberwinterthur (Kreis 2) / Talacker and Sankt Gallen is approximately 30 miles respectively 48 kilometers.
By car or train, the actual journey to Sankt Gallen is certainly longer, as only the direct route (as the crow flies) between Oberwinterthur (Kreis 2) / Talacker and Sankt Gallen has been calculated here.
Air line (approximately)
48 kilometers
26 nautical miles