| Name | Meaning | Gender | Origin |
|---|
| Jumbo | Unusually large person, animal or thing e.g. Jumbo Jet. From African 'jumba' meaning elephant. | Male | |
| Juniper | Juniper Tree | Female | English |
| Jurgen | German form of George
| Male | |
| Kahlan | after the character in Terry Goodkind's Sword of Truth novels | Unisex | |
| Kalina | Flower
| Female | |
| Kandy | Cutie
| Male | |
| Kari | curly hair | Male | Norse |
| Karinna | | Female | |
| Katherine | Pure. Used since third century A.D. Early Latin forms Katerina and Caterina became Katharine and Catherine. French Cateline and English Catlyn came into wider use during medieval period when variants multiplied.
| Female | Greek |
| Kawaii | | Unisex | |
| Kazak | | Male | Hebrew |
| Keifer | Barrelmaker Variation of Cooper. Surname.
| Male | |
| Ken | Male Barbie Doll. | Male | English |
| Kendra | Blend of Ken: (royal obligation:clear water) and Sandra: (protector of man) or Andrea: (manly or masculine).
| Female | English |
| Kenji | after Michael Kenji Shinoda, from the band Linkin Park | Male | Japanese |
| Kentuky | | Male | |
| Keo | | Unisex | Hebrew |
| Keondra | Goddess
| Female | |
| Khari | Queenly: Joyful Song: Born to rule and bring joy.
| Female | |
| Kiana | Variant of Kian. Ancient.
| Female | Modern |
| King | King's field. King is one of several titles occasionally used as given names.
| Male | English |
| Kingston | From the king's village or estate King's field. King is one of several titles occasionally used as given names.
| Male | English |
| Kismet | fate, destiny | Female | Word |
| Kitto | Greek and Latin, bearer of Christ | Male | Cornish |
| Kloey | Blooming. Variant of Chloe.
| Female | |