| Boulder to Jacksonville (Texas) | 787.71 mi (1,267.70 km) |
| Boulder to Jacksonville Beach (Florida) | 1,499.62 mi (2,413.40 km) |
| Boulder to James Island (South Carolina) | 1,489.25 mi (2,396.72 km) |
| Boulder to Jamestown (New York) | 1,357.59 mi (2,184.83 km) |
| Boulder to Jamestown (North Dakota) | 577.67 mi (929.67 km) |
| Boulder to Janesville (Wisconsin) | 860.58 mi (1,384.97 km) |
| Boulder to Jasmine Estates (Florida) | 1,516.65 mi (2,440.82 km) |
| Boulder to Jasper (Alabama) | 1,078.23 mi (1,735.24 km) |
| Boulder to Jasper (Indiana) | 985.07 mi (1,585.31 km) |
| Boulder to Jefferson (Georgia) | 1,257.00 mi (2,022.95 km) |
| Boulder to Jefferson (Louisiana) | 1,098.95 mi (1,768.59 km) |
| Boulder to Jefferson City (Missouri) | 705.75 mi (1,135.80 km) |
| Boulder to Jefferson Hills (Pennsylvania) | 1,332.56 mi (2,144.54 km) |
| Boulder to Jefferson Valley-Yorktown (New York) | 1,641.60 mi (2,641.89 km) |
| Boulder to Jeffersontown (Kentucky) | 1,060.41 mi (1,706.56 km) |
