| Isaura | | ee-SOW-rah (Spanish) | Portuguese, Spanish, Late Roman | |
| Isay | | - | Russian | |
| Isbel | | IZ-bel | English (Rare) | |
| Iseabail | | - | Scottish | |
| Isebella | | iz-ə-BEL-ə | English (Rare) | |
| Iser | | - | Yiddish | |
| Iseut | | - | Medieval English | |
| Isha | | - | Indian, Hindi, Marathi, Hinduism | |
| Ishbel | | - | Scottish | |
| Ishtar | | ISH-tahr (English) | Near Eastern Mythology | |
| Isiah | | ie-ZIE-ə | English | |
| IsibÉAl | | - | Irish | |
| Isidor | | EE-see-dawr (German) | German, Russian, Macedonian | |
| Isidora | | ee-see-DHO-rah (Spanish), ee-zee-DO-rah (Italian), iz-i-DAWR-ə (English) | Serbian, Macedonian, Spanish, Portuguese, Russian (Rare), Italian (Rare), English (Rare), Ancient Gr | |
| Isidore | | IZ-i-dawr (English), ee-zee-DOR (French) | English, French, Georgian, Jewish | |