Rex Boy
How popular is Rex?
#859 boy name in 2025
281 baby boys were named Rex in the US in 2025, making it the 859th most popular boy name.
36,045living people named Rex (est.)
62median age of people named Rex
60,590babies named Rex since 1880
1 in 11,798US babies born in 2025
Rex popularity over time
Boys Girls
| Rank in 2025 | #859 for boys (▼ 74 from 2024) |
|---|---|
| Babies in 2025 | 281 boys |
| 10-year trend | Falling (-25% babies vs 2015) |
| Earlier ranks | #679 in 2015, #681 in 2020 |
| Peak year | 1951 (1,503 boys) |
| Highest rank | #170 in 1951 |
| First recorded | 1880 |
| Boys vs girls (last 10 years) | 100% boys, 0% girls |
| Chance a classmate shares it | 0.2% in a class of 25 kids born in 2025 |
Where Rex is most popular
Babies named Rex per 1,000 boys born in each state, 2021 to 2025. Darker means more common.
Rex by decade
| Decade | Baby boys | Best rank |
|---|---|---|
| 1880s | 183 | #311 |
| 1890s | 305 | #298 |
| 1900s | 497 | #253 |
| 1910s | 3,253 | #229 |
| 1920s | 5,627 | #209 |
| 1930s | 5,949 | #194 |
| 1940s | 6,671 | #207 |
| 1950s | 13,499 | #170 |
| 1960s | 8,735 | #214 |
| 1970s | 3,359 | #362 |
| 1980s | 2,532 | #488 |
| 1990s | 1,740 | #660 |
| 2000s | 2,048 | #755 |
| 2010s | 3,945 | #607 |
| 2020s | 2,106 | #681 |
Boy names about as popular as Rex
Questions
- Is Rex a boy or girl name?
- Rex is mostly a boy name. Over the last 10 years, 100% of babies named Rex were boys.
- How popular is the name Rex?
- 281 baby boys were named Rex in the US in 2025, making it the 859th most popular boy name.
- When was Rex most popular?
- Rex peaked in 1951, when 1,503 boys were given the name. Its highest rank was #170 in 1951.
- How many people are named Rex?
- 60,590 babies have been named Rex in the US since 1880. We estimate about 36,045 of them are alive in 2026, with a median age of 62.
- Where is Rex most popular?
- From 2021 to 2025, Rex was most common in Utah, at 0.7 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.