| Johnston to Odessa (Texas) | 827.92 mi (1,332.41 km) |
| Johnston to Ogden (Utah) | 943.50 mi (1,518.41 km) |
| Johnston to Oildale (California) | 1,428.05 mi (2,298.23 km) |
| Johnston to Ojus (Florida) | 1,333.46 mi (2,146.00 km) |
| Johnston to Okemos (Michigan) | 481.41 mi (774.75 km) |
| Johnston to Oklahoma City (Oklahoma) | 476.11 mi (766.23 km) |
| Johnston to Okmulgee (Oklahoma) | 437.58 mi (704.21 km) |
| Johnston to Olathe (Kansas) | 202.41 mi (325.75 km) |
| Johnston to Old Jamestown (Missouri) | 267.70 mi (430.82 km) |
| Johnston to Oldsmar (Florida) | 1,129.55 mi (1,817.84 km) |
| Johnston to Olean (New York) | 785.97 mi (1,264.89 km) |
| Johnston to Olive Branch (Mississippi) | 510.12 mi (820.96 km) |
| Johnston to Olivehurst (California) | 1,469.42 mi (2,364.80 km) |
| Johnston to Olney (Maryland) | 891.90 mi (1,435.38 km) |
| Johnston to Olympia (Washington) | 1,478.18 mi (2,378.90 km) |
