| South Plainfield to Johnstown (Pennsylvania) | 237.42 mi (382.09 km) |
| South Plainfield to Joliet (Illinois) | 717.89 mi (1,155.34 km) |
| South Plainfield to Jonesboro (Arkansas) | 940.46 mi (1,513.53 km) |
| South Plainfield to Joplin (Missouri) | 1,105.30 mi (1,778.81 km) |
| South Plainfield to Joppatowne (Maryland) | 129.97 mi (209.16 km) |
| South Plainfield to Juana Díaz (Puerto Rico) | 1,625.65 mi (2,616.23 km) |
| South Plainfield to Junction City (Kansas) | 1,192.48 mi (1,919.11 km) |
| South Plainfield to Juneau (Alaska) | 2,834.33 mi (4,561.42 km) |
| South Plainfield to Jupiter (Florida) | 998.02 mi (1,606.15 km) |
| South Plainfield to Jupiter Farms (Florida) | 999.86 mi (1,609.13 km) |
| South Plainfield to Jurupa Valley (California) | 2,385.69 mi (3,839.39 km) |
| South Plainfield to Justice (Illinois) | 702.00 mi (1,129.77 km) |
| South Plainfield to Kahului (Hawaii) | 4,887.24 mi (7,865.26 km) |
| South Plainfield to Kailua (Hawaii) | 4,931.17 mi (7,935.95 km) |
| South Plainfield to Kalamazoo (Michigan) | 590.18 mi (949.81 km) |
