| Duncan to Jacksonville (Texas) | 235.16 mi (378.46 km) |
| Duncan to Jacksonville Beach (Florida) | 1,006.08 mi (1,619.12 km) |
| Duncan to James Island (South Carolina) | 1,040.49 mi (1,674.51 km) |
| Duncan to Jamestown (New York) | 1,136.10 mi (1,828.38 km) |
| Duncan to Jamestown (North Dakota) | 855.32 mi (1,376.50 km) |
| Duncan to Janesville (Wisconsin) | 739.35 mi (1,189.88 km) |
| Duncan to Jasmine Estates (Florida) | 994.93 mi (1,601.18 km) |
| Duncan to Jasper (Alabama) | 610.24 mi (982.09 km) |
| Duncan to Jasper (Indiana) | 665.12 mi (1,070.41 km) |
| Duncan to Jefferson (Georgia) | 816.73 mi (1,314.41 km) |
| Duncan to Jefferson (Louisiana) | 552.94 mi (889.87 km) |
| Duncan to Jefferson City (Missouri) | 423.04 mi (680.81 km) |
| Duncan to Jefferson Hills (Pennsylvania) | 1,061.69 mi (1,708.62 km) |
| Duncan to Jefferson Valley-Yorktown (New York) | 1,389.92 mi (2,236.86 km) |
| Duncan to Jeffersontown (Kentucky) | 731.56 mi (1,177.33 km) |
