Brennan Boy
How popular is Brennan?
#1,002 boy name in 2025
226 baby boys were named Brennan in the US in 2025, making it the 1002nd most popular boy name. Another 10 girls got the name (#9,454 for girls).
Brennan popularity over time
Boys Girls
| Rank in 2025 | #1,002 for boys (▲ 55 from 2024) |
|---|---|
| Babies in 2025 | 226 boys, 10 girls |
| 10-year trend | Falling fast (-67% babies vs 2015) |
| Earlier ranks | #444 in 2015, #764 in 2020 |
| Peak year | 2009 (1,464 boys) |
| Highest rank | #242 in 2009 |
| First recorded | 1916 |
| Boys vs girls (last 10 years) | 92% boys, 8% girls |
| Chance a classmate shares it | 0.2% in a class of 25 kids born in 2025 |
Brennan counting every spelling
Social Security counts each spelling as its own name. Adding together the spellings that sound alike, the Brennan family of names ranked #842 for boys in 2025 (#836 the year before), with 267 babies in all.
Spellings are grouped by how they sound, using our own rules, so a few groupings may not match how your family says the name.
Where Brennan is most popular
Babies named Brennan per 1,000 boys born in each state, 2021 to 2025. Darker means more common.
- Louisiana: 0.6 per 1,000 (61 boys)
- Mississippi: 0.4 per 1,000 (20 boys)
- Tennessee: 0.2 per 1,000 (43 boys)
- Virginia: 0.2 per 1,000 (43 boys)
- Pennsylvania: 0.2 per 1,000 (56 boys)
Brennan by decade
| Decade | Baby boys | Best rank |
|---|---|---|
| 1910s | 5 | #3,896 |
| 1940s | 6 | #3,297 |
| 1950s | 80 | #2,176 |
| 1960s | 394 | #944 |
| 1970s | 934 | #740 |
| 1980s | 2,719 | #421 |
| 1990s | 8,300 | #270 |
| 2000s | 11,745 | #242 |
| 2010s | 7,625 | #270 |
| 2020s | 1,450 | #764 |
Boy names about as popular as Brennan
Questions
- Is Brennan a boy or girl name?
- Brennan is mostly a boy name. Over the last 10 years, 92% of babies named Brennan were boys.
- How popular is the name Brennan?
- 226 baby boys were named Brennan in the US in 2025, making it the 1002nd most popular boy name. Another 10 girls got the name (#9,454 for girls).
- When was Brennan most popular?
- Brennan peaked in 2009, when 1,464 boys were given the name. Its highest rank was #242 in 2009.
- How many people are named Brennan?
- 35,487 babies have been named Brennan in the US since 1880. We estimate about 34,665 of them are alive in 2026, with a median age of 23.
- Where is Brennan most popular?
- From 2021 to 2025, Brennan was most common in Louisiana, at 0.6 of every 1,000 boys born there.
Source: Social Security Administration baby name data, 1880 to 2025 (names given to at least 5 babies of a sex in a year). Living-people and median-age figures are our estimates using US life tables. How we calculate.