The calculated distance (air line) between Bülach and Zürich (Kreis 6) is approximately 9 miles respectively 14 kilometers.
By car or train, the actual journey to Zürich (Kreis 6) is certainly longer, as only the direct route (as the crow flies) between Bülach and Zürich (Kreis 6) has been calculated here.
Air line (approximately)
14 kilometers
8 nautical miles