The calculated distance (air line) between Sirnach and Zürich (Kreis 2) is approximately 24 miles respectively 38 kilometers.
By car or train, the actual journey to Zürich (Kreis 2) is certainly longer, as only the direct route (as the crow flies) between Sirnach and Zürich (Kreis 2) has been calculated here.
Air line (approximately)
38 kilometers
21 nautical miles