| Gustav | | GOO-stahf (German) | Swedish, Norwegian, Danish, German | |
| Gustavo | | goo-STAH-vo (Italian, Spanish) | Italian, Spanish, Portuguese | |
| Gustaw | | GUWS-tahf | Polish | |
| Gusti | | - | Indonesian, Balinese | |
| Guto | | GI-taw | Welsh | |
| Gutxi | | - | Basque | |
| Guy | | GIE (English), GEE (French) | English, French | |
| Gwalchmei | | - | Welsh Mythology | |
| Gwallter | | - | Welsh | |
| Gwandoya | | - | Eastern African, Ganda | |
| Gwawr | | - | Welsh | |
| Gwen | | GWEN | Welsh, English | |
| Gwenda | | GWEN-də (English) | Welsh, English | |
| Gwendolen | | GWEN-də-lin (English) | Welsh | |
| Gwendoline | | GWEN-də-lien (English), GWEN-də-leen (English) | Welsh, English (British), French | |