| Name | Meaning | Gender | Origin |
|---|
| Jimmy | supplanter | Male | English |
| Jip | | Male | |
| Jodie | From Judith - Admired and praised | Unisex | |
| Johnn | Variant of the Hebrew John Jehovah has been gracious: has shown favor.
| Male | |
| Johnson | Son of John
| Male | English |
| Johnston | From John's farm
| Male | |
| Joker | | Male | Hebrew |
| Joli | Cheerful; Pretty. | Unisex | English |
| Jon | God is gracious; or gift of Jehovah | Male | English |
| Jonas | Dove. Variant of Hebrew Jonah.
| Male | Greek |
| Jr. | | Unisex | Hebrew |
| Justin | just, true | Male | Latin |
| Justine | just, true | Female | |
| K.C. | Kitchen Cat | Unisex | |
| Kacee | Cathasaigh's Heir | Unisex | English |
| Kaci | Cathasaigh's Heir | Unisex | English |
| Kadi | Rhyming Variant Of Katy Or Cady. | Unisex | English |
| Kady | first | Female | Irish |
| Kalila | beloved | Female | Arabic |
| Kally | Modern Variant Of Callie. | Unisex | English |
| Kalyn | Slender | Unisex | English |
| Kameron | Scottish surname, crooked nose | Male | Spelling |
| Kane | tribute, warrior; the doubly-accomplished, golden; man, the eastern sky; beautiful | Male | Celtic |
| Karisma | Favor; Gift;Carisma. | Unisex | English |
| Katelyn | pure | Female | Spelling |