The calculated distance (air line) between Onex and Zürich (Kreis 6) is approximately 143 miles respectively 229 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 Onex and Zürich (Kreis 6) has been calculated here.
Air line (approximately)
229 kilometers
124 nautical miles