| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Isolda | i-ZOL-də (English), i-SOL-də (English) | Arthurian Romance | ||
| Isolde | i-ZOL-də (English), i-SOL-də (English), ee-ZAWL-du (German) | English (Rare), German, Arthurian Romance | ||
| IstvÁN | - | Hungarian | ||
| IvÁN | - | Spanish, Hungarian | ||
| Izabella | ee-zah-BEL-lah (Polish) | Hungarian, Polish | ||
| IzidÓRa | - | Hungarian (Rare) | ||
| IzsÁK | EE-zhahk | Hungarian |