| Hackettstown to Dover (New Hampshire) | 258.69 mi (416.32 km) |
| Hackettstown to Dover (New Jersey) | 14.07 mi (22.65 km) |
| Hackettstown to Dover (Ohio) | 349.27 mi (562.09 km) |
| Hackettstown to Downers Grove (Illinois) | 686.88 mi (1,105.42 km) |
| Hackettstown to Downey (California) | 2,399.56 mi (3,861.71 km) |
| Hackettstown to Dranesville (Virginia) | 186.14 mi (299.56 km) |
| Hackettstown to Draper (Utah) | 1,926.17 mi (3,099.87 km) |
| Hackettstown to Drexel Heights (Arizona) | 2,083.30 mi (3,352.75 km) |
| Hackettstown to Drexel Hill (Pennsylvania) | 67.37 mi (108.42 km) |
| Hackettstown to Duarte (California) | 2,383.79 mi (3,836.34 km) |
| Hackettstown to Dublin (California) | 2,496.28 mi (4,017.38 km) |
| Hackettstown to Dublin (Georgia) | 728.51 mi (1,172.42 km) |
| Hackettstown to Dublin (Ohio) | 440.05 mi (708.20 km) |
| Hackettstown to Dubuque (Iowa) | 826.18 mi (1,329.61 km) |
| Hackettstown to Duluth (Georgia) | 696.08 mi (1,120.24 km) |
