| Name | Meaning | Gender | Origin |
|---|
| Ink | | Unisex | |
| Inka | Mythical Fertility God | Unisex | German |
| Inky | | Unisex | Hebrew |
| Iris | rainbow, a play of colours | Female | |
| Isabella White | | Female | |
| Isis | throne | Female | Egyptian |
| Itsy | | Unisex | Hebrew |
| Jabba | | Unisex | Hebrew |
| Jada | wise | Female | Spanish |
| Jade | Jewel. Courageous and adoring.
| Female | Spanish |
| Jamie | Feminine of James | Female | Scottish |
| Jar Jar Binks | | Unisex | Hebrew |
| Java Bean | | Unisex | Hebrew |
| Jelly | | Unisex | Hebrew |
| Jet Black | | Unisex | |
| Jewel | Jewel
| Female | Word |
| Jezebel | follower of idols | Female | Hebrew |
| Jinx | Charm, Spell | Female | Latin |
| Josie | From Josephine - She shall add. | Female | English |
| Jovi | after Jon Bon Jovi | Unisex | |
| Joy | From Joyce - Gay and joyful | Female | Word |
| Juice | | Unisex | Hebrew |
| Juniper | Juniper Tree | Female | English |
| Juno | queen of the heavens | Female | Latin |
| Kaiser | Any of the emperors of The Holy Roman Empire, Austria or Germany | Unisex | |