By decade. Change compares yearly averages, so the current partial decade is on equal
footing. Best rank is the name's best yearly rank within the decade.
Where Brennan is most popular
Boys named Brennan per 1,000 boys born in
each state, 2021–2025. National average: 0.131 per 1,000.
Strongest in Louisiana, Mississippi, and Tennessee.
Vs national average well below below near national above well above no data
All 50 states and DC, sorted by rate. Counts are boys named Brennan born
2021–2025; the per-1,000 rate makes states of different sizes
comparable, and the last column shows each state against the national average.
State counts come from the Social Security Administration's state files, which omit any
state-year with fewer than five babies of a name, so small states can undercount slightly.
The story of Brennan
Brennan is uncommon for boys in the United States, ranked #1,003 in 2025 with 226 babies given the name. It is currently declining compared with a decade ago.
Since 1916, 35,487 American babies have been named Brennan, about 94% boys and 6% girls, making it a genuinely unisex name. Its peak came in 2009, when 1,550 newborns received the name, the signature sound of the 2000s.
The chart above shows the full history: the popularity view (births per 1,000 babies) is the honest comparison across generations, since total US births have changed enormously since 1880. Switch to the rank view to see where Brennan stood among all boys' names in any year, or use the compare tool to plot it against other names.