Cai
Cai was the 2113th most popular name for boys in 2025, given to 69 babies. Its best year was 2022, when it ranked 1612th with 108 babies. Over the last ten years it has moved down 297 places. More babies were named Cai in the 2010s than in any other decade.
Meaning (as Kai) Origin uncertain · Scandinavian, Frisian, Hawaiian, Welsh
- Rank in 2025
- #2,113 boys, up 5 places since 2020
- Babies in 2025
- 69boys
- Girls and boys
- 19% girls, 81% boys2021–2025
- Peak year
- 2022108 babies
- Total since 1880
- 1,945babies recorded
What does the name Cai mean?
Cai is a spelling of Kai, pronounced the same way, so it shares Kai's meaning and origin.
Kai has several separate sources that happen to share a spelling. In Scandinavia and Germany, Kai or Kaj has been used for centuries; it may come from a Latin name like Caius or, in Frisian, from pet forms of longer names. Welsh Cai, Sir Kay of Arthurian legend, is another Latin-derived form. In Hawaiian, kai is the common word for 'sea', and many American parents choose the name with that meaning in mind. Japanese and other languages have their own unrelated names and words spelled Kai.
kai (Hawaiian, “sea”)Caius (Latin, “Roman name (possible source of Scandinavian Kaj)”)
How sure is this? Uncertain. Several unrelated origins; the Scandinavian and German name's ultimate source is not settled. The Hawaiian word meaning is clear, but whether a given family uses it in that sense varies.
See also: Scandinavian names.
Sources for this meaning
- Wiktionary, entry 'Kai', Wiktionary (Wikimedia Foundation); facts restated, no text reused
- Wiktionary, entry 'kai', Wiktionary (Wikimedia Foundation); facts restated, no text reused
- Wikipedia, 'Kai (name)', Wikipedia (Wikimedia Foundation); facts restated, no text reused
Cai popularity since 1880
| Year | Rank (girls) | Rank (boys) | Babies (girls) | Babies (boys) |
|---|---|---|---|---|
| 2025 | #8,457 | #2,113 | 12 | 69 |
| 2020 | #3,789 | #2,118 | 38 | 66 |
| 2010 | #11,434 | #3,023 | 9 | 38 |
| 2000 | #12,005 | #4,610 | 7 | 16 |
| 1990 | — | #5,037 | — | 10 |
| 1980 | — | — | — | — |
| 1970 | — | — | — | — |
| 1960 | — | — | — | — |
| 1950 | — | — | — | — |
| 1940 | — | — | — | — |
| 1930 | — | — | — | — |
| 1920 | — | — | — | — |
| 1910 | — | — | — | — |
| 1900 | — | — | — | — |
| 1890 | — | — | — | — |
| 1880 | — | — | — | — |
How popular is Cai, counting every spelling?
Cai is a spelling of Kai, a name family that ranked #96 for boys in 2025 once every spelling is counted together, compared with #2,113 for Cai on its own. Together these spellings went to 3,837 boys in 2025.
| Spelling | Babies 2025 | Official rank | Babies 2021–2025 |
|---|---|---|---|
| Kai | 3,768 | #93 | 23,060 |
| Cai | 69 | #2,113 | 433 |
Spellings count together when they sound the same in American English and are used for the same sex; nicknames and forms that sound different (such as Theo and Theodore) are kept apart. How we group spellings.
How many kids will share the name Cai?
69 of the 3,606,400 babies born in the US in 2025 were named Cai (0.02 per 1,000 births). For a boy named Cai born in 2025, the chance that another child with the same name is in a class of 20 children the same age is under 1 in 50. If every grade liked the name as much as the 2025 babies do, only about one elementary school in 122 (of 430 pupils) would have a child named Cai.
Shares of all registered births (NCHS); classes assumed to be children born the same year. How we estimate this.
How old are people named Cai?
About 1,400 people born in the US named Cai are alive today, with a median age of 10; half are between 5 and 16. That makes Cai a young name: most people with it are children.
Babies given the name each year (SSA) times the share of that birth year still alive (SSA life tables). Counts people born in the US only. Method.
Cai by state
How common Cai was among boys born in each state in 2021–2025. It is notably more common than nationally in Florida (1.7×), Georgia (1.6×). In 35 states fewer than five boys a year got the name, too few for SSA to publish, so those states show as zero.
Names with a similar history
These names rose and fell in step with Cai: their share of US boys followed the most similar curve since 1880. If you like Cai, they share its era and feel.
Questions about the name Cai
What does Cai mean?
The origin of Kai is uncertain: several unrelated origins; the Scandinavian and German name's ultimate source is not settled. The Hawaiian word meaning is clear, but whether a given family uses it in that sense varies.
How popular is the name Cai?
Cai was the 2113th most popular name for boys in 2025, given to 69 babies. Its best year was 2022, when it ranked 1612th with 108 babies. Over the last ten years it has moved down 297 places. More babies were named Cai in the 2010s than in any other decade.
Is Cai a boy or girl name?
In 2021–2025, 19% girls, 81% boys given the name Cai in the US.
Where is Cai most popular?
In 2021–2025, Cai was most common in Florida (0.09 per 1,000 boys), followed by Georgia and Louisiana.