| Duncan to Friendswood (Texas) | 382.34 mi (615.32 km) |
| Duncan to Frisco (Texas) | 114.62 mi (184.46 km) |
| Duncan to Front Royal (Virginia) | 1,131.60 mi (1,821.13 km) |
| Duncan to Fruit Cove (Florida) | 998.89 mi (1,607.56 km) |
| Duncan to Fruita (Colorado) | 676.68 mi (1,089.02 km) |
| Duncan to Fruitville (Florida) | 1,041.06 mi (1,675.43 km) |
| Duncan to Fuller Heights (Florida) | 1,044.29 mi (1,680.62 km) |
| Duncan to Fullerton (California) | 1,142.15 mi (1,838.11 km) |
| Duncan to Fullerton (Pennsylvania) | 1,294.29 mi (2,082.95 km) |
| Duncan to Fulshear (Texas) | 355.58 mi (572.26 km) |
| Duncan to Fulton (Missouri) | 445.07 mi (716.27 km) |
| Duncan to Fulton (New York) | 1,299.91 mi (2,092.00 km) |
| Duncan to Fuquay-Varina (North Carolina) | 1,083.33 mi (1,743.46 km) |
| Duncan to Gadsden (Alabama) | 680.36 mi (1,094.94 km) |
| Duncan to Gaffney (South Carolina) | 922.51 mi (1,484.64 km) |
