| Gaithersburg to Jeffersonville (Indiana) | 460.67 mi (741.38 km) |
| Gaithersburg to Jenison (Michigan) | 518.79 mi (834.90 km) |
| Gaithersburg to Jenks (Oklahoma) | 1,048.03 mi (1,686.64 km) |
| Gaithersburg to Jennings (Missouri) | 701.47 mi (1,128.91 km) |
| Gaithersburg to Jensen Beach (Florida) | 839.89 mi (1,351.68 km) |
| Gaithersburg to Jericho (New York) | 225.47 mi (362.85 km) |
| Gaithersburg to Jerome (Idaho) | 1,947.02 mi (3,133.43 km) |
| Gaithersburg to Jersey City (New Jersey) | 199.31 mi (320.77 km) |
| Gaithersburg to Jessup (Maryland) | 23.38 mi (37.63 km) |
| Gaithersburg to Johns Creek (Georgia) | 523.72 mi (842.85 km) |
| Gaithersburg to Johnson City (New York) | 216.64 mi (348.64 km) |
| Gaithersburg to Johnson City (Tennessee) | 341.95 mi (550.31 km) |
| Gaithersburg to Johnston (Iowa) | 884.87 mi (1,424.06 km) |
| Gaithersburg to Johnstown (Colorado) | 1,469.86 mi (2,365.52 km) |
| Gaithersburg to Johnstown (Pennsylvania) | 122.46 mi (197.08 km) |
