Kiernan is an uncommon name used for both girls and boys that peaked in 2008 and has grown less common since.
Kiernan is predominantly a boy name. In 2025 it ranked #3,409 among boys (34) and #10,519 among girls (9) — overall #6,257 across all names. The charts below show girls and boys separately.
| Year | U.S. births | U.S. + territories | ♀ Rank | ♂ Rank |
|---|---|---|---|---|
| 2025 | 43 | 43 | #10,519 | #3,409 |
| 2024 | 45 | 45 | #14,414 | #3,137 |
| 2023 | 41 | 41 | #8,741 | #3,848 |
| 2022 | 45 | 45 | #7,857 | #3,661 |
| 2021 | 58 | 58 | #6,853 | #3,003 |
| 2020 | 54 | 54 | #5,759 | #3,381 |
| 2019 | 58 | 58 | #4,719 | #3,765 |
| 2018 | 62 | 62 | #6,393 | #2,823 |
| 2017 | 79 | 79 | #5,254 | #2,404 |
| 2016 | 45 | 45 | #8,647 | #3,484 |
| 2015 | 51 | 51 | #9,827 | #2,943 |
| 2014 | 56 | 56 | #8,294 | #2,834 |
| 2013 | 50 | 50 | #7,582 | #3,239 |
| 2012 | 52 | 52 | #10,089 | #2,891 |
| 2011 | 74 | 74 | #8,427 | #2,188 |
| 2010 | 96 | 96 | #6,073 | #1,920 |
| 2009 | 89 | 89 | #6,003 | #2,085 |
| 2008 | 104 | 104 | #5,372 | #1,888 |
| 2007 | 87 | 87 | #6,454 | #2,081 |
| 2006 | 65 | 65 | #7,687 | #2,498 |
| 2005 | 84 | 84 | #7,001 | #1,899 |
| 2004 | 75 | 75 | #6,371 | #2,120 |
| 2003 | 94 | 94 | #5,028 | #1,754 |
| 2002 | 101 | 101 | #3,852 | #1,732 |
| 2001 | 88 | 88 | #4,383 | #1,854 |
| 2000 | 92 | 92 | #4,894 | #1,694 |
| 1999 | 74 | 74 | #4,388 | #2,009 |
| 1998 | 59 | 59 | #5,251 | #2,296 |
| 1997 | 57 | — | #5,757 | #2,190 |
| 1996 | 72 | — | #4,673 | #1,832 |
| 1995 | 49 | — | #6,119 | #2,325 |
| 1994 | 52 | — | #6,498 | #2,151 |
| 1993 | 48 | — | #5,809 | #2,376 |
| 1992 | 29 | — | #9,964 | #3,166 |
| 1991 | 33 | — | #6,798 | #3,176 |
| 1990 | 16 | — | — | #3,703 |
| 1989 | 14 | — | — | #3,920 |
| 1988 | 17 | — | #12,816 | #4,061 |
| 1987 | 22 | — | #8,368 | #3,438 |
| 1986 | 7 | — | — | #5,678 |
| 1985 | 15 | — | #11,538 | #4,217 |
| 1984 | 8 | — | — | #4,784 |
| 1983 | 10 | — | #11,096 | #6,811 |
| 1982 | 20 | — | #7,177 | #3,824 |
| 1981 | 7 | — | — | #5,229 |
| 1980 | 6 | — | #9,664 | — |
| 1978 | 11 | — | #9,077 | #6,329 |
| 1976 | 5 | — | — | #6,064 |
| 1972 | 5 | — | #8,879 | — |
| 1971 | 5 | — | — | #5,307 |
| 1970 | 5 | — | — | #5,106 |
| 1969 | 9 | — | — | #3,201 |
| 1957 | 5 | — | — | #4,284 |