| Name | Meaning | Gender | Origin |
|---|
| Jack | From John - God's gracious gift | Male | English |
| Jackjack | | Unisex | Hebrew |
| Jackson | Son of Jack | Male | English |
| Jake | From Jacob - To fill the place of another | Male | Hebrew |
| Jasper | Black stone
| Male | Persian |
| Jasper | Black stone
| Male | Persian |
| Jasper | Black stone
| Male | Persian |
| Jax | God has been gracious: has shown favor. Based on John or Jacques.
| Male | Modern |
| Jedda | | Male | Hebrew |
| Jess | Gift | Male | English |
| Jesse | wealthy | Male | Hebrew |
| Jessy | God's Gracious Gift | Unisex | Hebrew |
| Jingles | | Unisex | Hebrew |
| Joey | Abbreviation of Joseph.
| Male | |
| Joey | Abbreviation of Joseph.
| Male | |
| Kingston | From the king's village or estate King's field. King is one of several titles occasionally used as given names.
| Male | English |
| Kit | Nickname for Christopher. Frontiersman Kit Carson.
| Male | English |
| Kitkat | | Unisex | Hebrew |
| Kiwi | | Unisex | Hebrew |
| Kujo | | Unisex | |
| Lenny | brave lion | Male | English |
| Light | | Male | |
| Lucky | Having good luck. | Male | Word |
| Luigi | Famous fighter
| Male | Italian |
| Mac | Son of
| Male | Scottish |