Caius Boy
How popular is Caius?
#927 boy name in 2025
254 baby boys were named Caius in the US in 2025, making it the 927th most popular boy name.
Caius popularity over time
| Rank in 2025 | #927 for boys (▲ 133 from 2024) |
|---|---|
| Babies in 2025 | 254 boys |
| 10-year trend | Rising fast (+84% babies vs 2015) |
| Earlier ranks | #1,287 in 2015, #1,209 in 2020 |
| Peak year | 2025 (254 boys) |
| Highest rank | #927 in 2025 |
| First recorded | 1994 |
| 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 |
Caius counting every spelling
Social Security counts each spelling as its own name. Adding together the spellings that sound alike, the Kaius family of names ranked #583 for boys in 2025 (#655 the year before), with 470 babies in all.
| Spelling | Boys in 2025 | Share |
|---|---|---|
| Kaius | 216 | 46% |
| Caius | 254 | 54% |
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 Caius is most popular
Babies named Caius per 1,000 boys born in each state, 2021 to 2025. Darker means more common.
Caius by decade
Boy names about as popular as Caius
Questions
- Is Caius a boy or girl name?
- Caius is mostly a boy name. Over the last 10 years, 100% of babies named Caius were boys.
- How popular is the name Caius?
- 254 baby boys were named Caius in the US in 2025, making it the 927th most popular boy name.
- When was Caius most popular?
- Caius peaked in 2025, when 254 boys were given the name. Its highest rank was #927 in 2025.
- How many people are named Caius?
- 2,329 babies have been named Caius in the US since 1880. We estimate about 2,316 of them are alive in 2026, with a median age of 7.
- Where is Caius most popular?
- From 2021 to 2025, Caius was most common in Oklahoma, at 0.2 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.