| Duncan to Kaneohe (Hawaii) | 3,710.83 mi (5,972.00 km) |
| Duncan to Kankakee (Illinois) | 711.05 mi (1,144.33 km) |
| Duncan to Kannapolis (North Carolina) | 978.83 mi (1,575.28 km) |
| Duncan to Kansas City (Kansas) | 362.05 mi (582.67 km) |
| Duncan to Kansas City (Missouri) | 367.28 mi (591.08 km) |
| Duncan to Kapaa (Hawaii) | 3,777.56 mi (6,079.39 km) |
| Duncan to Kapolei (Hawaii) | 3,728.74 mi (6,000.82 km) |
| Duncan to Katy (Texas) | 350.13 mi (563.49 km) |
| Duncan to Kaukauna (Wisconsin) | 846.26 mi (1,361.93 km) |
| Duncan to Kaysville (Utah) | 885.75 mi (1,425.47 km) |
| Duncan to Kearney (Missouri) | 386.33 mi (621.74 km) |
| Duncan to Kearney (Nebraska) | 430.35 mi (692.57 km) |
| Duncan to Kearns (Utah) | 877.73 mi (1,412.57 km) |
| Duncan to Kearny (New Jersey) | 1,365.98 mi (2,198.33 km) |
| Duncan to Keene (New Hampshire) | 1,490.40 mi (2,398.57 km) |
