| Duncan to Frederick (Maryland) | 1,178.20 mi (1,896.13 km) |
| Duncan to Fredericksburg (Texas) | 300.55 mi (483.68 km) |
| Duncan to Fredericksburg (Virginia) | 1,162.81 mi (1,871.35 km) |
| Duncan to Frederickson (Washington) | 1,534.01 mi (2,468.76 km) |
| Duncan to Freeport (Illinois) | 697.75 mi (1,122.91 km) |
| Duncan to Freeport (New York) | 1,392.32 mi (2,240.73 km) |
| Duncan to Freeport (Texas) | 414.83 mi (667.60 km) |
| Duncan to Fremont (California) | 1,356.41 mi (2,182.93 km) |
| Duncan to Fremont (Nebraska) | 482.99 mi (777.29 km) |
| Duncan to Fremont (Ohio) | 932.14 mi (1,500.13 km) |
| Duncan to French Valley (California) | 1,098.32 mi (1,767.58 km) |
| Duncan to Fresno (California) | 1,234.84 mi (1,987.28 km) |
| Duncan to Fresno (Texas) | 374.41 mi (602.56 km) |
| Duncan to Fridley (Minnesota) | 768.99 mi (1,237.57 km) |
| Duncan to Friendly (Maryland) | 1,194.81 mi (1,922.86 km) |
