| Mason City to Jeffersontown (Kentucky) | 525.45 mi (845.62 km) |
| Mason City to Jeffersonville (Indiana) | 513.94 mi (827.11 km) |
| Mason City to Jenison (Michigan) | 372.65 mi (599.72 km) |
| Mason City to Jenks (Oklahoma) | 515.59 mi (829.76 km) |
| Mason City to Jennings (Missouri) | 341.96 mi (550.33 km) |
| Mason City to Jensen Beach (Florida) | 1,316.63 mi (2,118.91 km) |
| Mason City to Jericho (New York) | 1,020.53 mi (1,642.38 km) |
| Mason City to Jerome (Idaho) | 1,075.81 mi (1,731.35 km) |
| Mason City to Jersey City (New Jersey) | 995.30 mi (1,601.78 km) |
| Mason City to Jessup (Maryland) | 896.25 mi (1,442.38 km) |
| Mason City to Johns Creek (Georgia) | 794.42 mi (1,278.49 km) |
| Mason City to Johnson City (New York) | 877.48 mi (1,412.16 km) |
| Mason City to Johnson City (Tennessee) | 741.65 mi (1,193.56 km) |
| Mason City to Johnston (Iowa) | 104.20 mi (167.69 km) |
| Mason City to Johnstown (Colorado) | 635.09 mi (1,022.09 km) |
