The calculated distance (air line) between Zürich (Kreis 4) / Hard and Schaffhausen is approximately 22 miles respectively 36 kilometers.
By car or train, the actual journey to Schaffhausen is certainly longer, as only the direct route (as the crow flies) between Zürich (Kreis 4) / Hard and Schaffhausen has been calculated here.
Air line (approximately)
36 kilometers
20 nautical miles