| Cooperstown Dapto | Eastern Australia Time | -14:00 |
| Cooperstown Donji Vinjani | Central European Time | -06:00 |
| Cooperstown Dardanelle | Central Time | 01:00 |
| Cooperstown Don Mueang | Indochina Time | -11:00 |
| Cooperstown Darch | Western Australia Time | -12:00 |
| Cooperstown Domžale | Central European Time | -06:00 |
| Cooperstown Darasaguppe | India Standard Time | -09:30 |
| Cooperstown Domodossola | Central European Time | -06:00 |
| Cooperstown Darlinghurst | Eastern Australia Time | -14:00 |
| Cooperstown Dolphin Coast | South Africa Standard Time | -06:00 |
| Cooperstown Colares | Western European Time | -05:00 |
| Cooperstown Dolynka | Eastern European Time | -07:00 |
| Cooperstown Cold Spring | Eastern Time | 00:00 |
| Cooperstown Dolus-d'Oléron | Central European Time | -06:00 |
| Cooperstown Coldwater | Eastern Time | 00:00 |
| Cooperstown Dolo | Central European Time | -06:00 |
| Cooperstown Coina | Western European Time | -05:00 |
| Cooperstown Docklands | Eastern Australia Time | -14:00 |
| Cooperstown Coffeyville | Central Time | 01:00 |
| Cooperstown Doesburg | Central European Time | -06:00 |
| Cooperstown Chandigadh | India Standard Time | -09:30 |
| Cooperstown Chandrapur | Nepal Time | -09:45 |
| Cooperstown Collingwood | Eastern Australia Time | -14:00 |
| Cooperstown Collingswood | Eastern Time | 00:00 |
| Cooperstown Collegeville | Eastern Time | 00:00 |
| Cooperstown Cologna Veneta | Central European Time | -06:00 |
| Cooperstown Cologne | Central European Time | -06:00 |
| Cooperstown College Place | Pacific Time | 03:00 |
| Cooperstown Colfax | Pacific Time | 03:00 |
| Cooperstown Colborne | Eastern Time | 00:00 |
| Cooperstown Chagford | United Kingdom Time | -05:00 |
| Cooperstown Chadstone | Eastern Australia Time | -14:00 |
| Cooperstown Chae Ramae | Indochina Time | -11:00 |
| Cooperstown Chakpachuria | India Standard Time | -09:30 |
| Cooperstown Chandanpur | India Standard Time | -09:30 |
| Cooperstown Chamblee | Eastern Time | 00:00 |
| Cooperstown Chamonix | Central European Time | -06:00 |
| Cooperstown Chalong | Indochina Time | -11:00 |