| Guyancourt Luanda | West Africa Time | 01:00 |
| Guyancourt Quezon City | Philippine Time | -06:00 |
| Guyancourt Addis Ababa | East Africa Time | -01:00 |
| Guyancourt Nairobi | East Africa Time | -01:00 |
| Guyancourt Chicago | Central Time | 07:00 |
| Guyancourt Salvador | Brasilia Time | 05:00 |
| Guyancourt Jaipur | India Standard Time | -03:30 |
| Guyancourt Dar es Salaam | East Africa Time | -01:00 |
| Guyancourt Lanzhou | China Time | -06:00 |
| Guyancourt Incheon | Korean Time | -07:00 |
| Guyancourt Yunfu | China Time | -06:00 |
| Guyancourt Navi Mumbai | India Standard Time | -03:30 |
| Guyancourt Toronto | Eastern Time | 06:00 |
| Guyancourt Basrah | Arabian Time | -01:00 |
| Guyancourt Osaka | Japan Time | -07:00 |
| Guyancourt Mogadishu | East Africa Time | -01:00 |
| Guyancourt Daegu | Korean Time | -07:00 |
| Guyancourt Faisalabad | Pakistan Time | -03:00 |
| Guyancourt Izmir | Turkey Time | -01:00 |
| Guyancourt Dakar | Greenwich Mean Time | 02:00 |
| Guyancourt Lucknow | India Standard Time | -03:30 |
| Guyancourt Giza | Eastern European Time | 00:00 |
| Guyancourt Fortaleza | Brasilia Time | 05:00 |
| Guyancourt Cali | Colombia Time | 07:00 |
| Guyancourt Surabaya | Western Indonesia Time | -05:00 |
| Guyancourt Belo Horizonte | Brasilia Time | 05:00 |
| Guyancourt Nanchang | China Time | -06:00 |
| Guyancourt Rome | Central European Time | 00:00 |
| Guyancourt Mashhad | Iran Time | -02:30 |
| Guyancourt Borough of Brooklyn | Eastern Time | 06:00 |
| Guyancourt Houston | Central Time | 07:00 |
| Guyancourt Queens | Eastern Time | 06:00 |
| Guyancourt Nagpur | India Standard Time | -03:30 |
| Guyancourt Maracaibo | Venezuela Time | 06:00 |
| Guyancourt Brasília | Brasilia Time | 05:00 |
| Guyancourt Santo Domingo | Atlantic Time | 06:00 |
| Guyancourt Nagoya | Japan Time | -07:00 |
| Guyancourt Brisbane | Eastern Australia Time | -08:00 |
| Guyancourt Havana | Cuba Time | 06:00 |
| Guyancourt Paris | Central European Time | 00:00 |
| Guyancourt Al Mawşil al Jadīdah | Arabian Time | -01:00 |
| Guyancourt Johannesburg | South Africa Standard Time | 00:00 |
| Guyancourt Kowloon | Hong Kong Time | -06:00 |
| Guyancourt Al Başrah al Qadīmah | Arabian Time | -01:00 |
| Guyancourt Almaty | East Kazakhstan Time | -04:00 |
| Guyancourt Medellin | Colombia Time | 07:00 |
| Guyancourt Tashkent | Uzbekistan Time | -03:00 |
| Guyancourt Algiers | Central European Time | 01:00 |
| Guyancourt Khartoum | Central Africa Time | 00:00 |
| Guyancourt Accra | Greenwich Mean Time | 02:00 |