The calculated distance (air line) between Kópavogur and Sauðárkrókur is approximately 131 miles respectively 211 kilometers.
By car or train, the actual journey to Sauðárkrókur is certainly longer, as only the direct route (as the crow flies) between Kópavogur and Sauðárkrókur has been calculated here.
Air line (approximately)
211 kilometers
114 nautical miles