Kayin is a rare name used for both girls and boys that peaked in 2005 and has since faded.
Kayin is predominantly a boy name. In 2025 it ranked #9,319 for boy births in the United States (and #19,235 across all names), given to 8 babies. Kayin was first reported in SSA data in 1977 and peaked in 2001 (31 births).
| Year | U.S. births | U.S. + territories | ♀ Rank | ♂ Rank |
|---|---|---|---|---|
| 2025 | 8 | 8 | — | #9,319 |
| 2023 | 19 | 19 | #11,706 | #7,522 |
| 2022 | 18 | 18 | #12,897 | #7,509 |
| 2021 | 9 | 9 | — | #8,518 |
| 2020 | 8 | 8 | — | #9,148 |
| 2019 | 10 | 10 | — | #7,936 |
| 2018 | 11 | 11 | — | #7,377 |
| 2017 | 17 | 17 | — | #5,409 |
| 2016 | 23 | 23 | — | #4,402 |
| 2015 | 8 | 8 | — | #9,165 |
| 2014 | 15 | 15 | #17,869 | #7,855 |
| 2013 | 25 | 25 | #13,899 | #5,076 |
| 2012 | 23 | 23 | — | #4,325 |
| 2011 | 21 | 21 | #18,189 | #5,561 |
| 2010 | 23 | 23 | #18,417 | #5,142 |
| 2009 | 24 | 24 | — | #4,218 |
| 2008 | 31 | 31 | — | #3,530 |
| 2007 | 32 | 32 | #19,041 | #3,844 |
| 2006 | 33 | 33 | #12,977 | #3,945 |
| 2005 | 39 | 39 | #9,786 | #3,492 |
| 2004 | 36 | 36 | #15,092 | #3,250 |
| 2003 | 22 | 22 | — | #3,910 |
| 2002 | 30 | 30 | #11,633 | #3,861 |
| 2001 | 38 | 38 | #12,730 | #2,964 |
| 2000 | 21 | 21 | — | #3,856 |
| 1999 | 25 | 25 | — | #3,232 |
| 1998 | 13 | 13 | — | #5,034 |
| 1997 | 10 | — | — | #5,877 |
| 1996 | 14 | — | — | #4,509 |
| 1994 | 9 | — | — | #6,104 |
| 1993 | 8 | — | — | #6,539 |
| 1977 | 7 | — | — | #4,870 |