The calculated distance (air line) between Flawil and Zürich (Kreis 10) is approximately 32 miles respectively 51 kilometers.
By car or train, the actual journey to Zürich (Kreis 10) is certainly longer, as only the direct route (as the crow flies) between Flawil and Zürich (Kreis 10) has been calculated here.
Air line (approximately)
51 kilometers
28 nautical miles