Koi
Masculine · “carp”
Koi is given to both — 813 boys and 669 girls since 1880. See Koi as a girl nameSee other names given to both
Koi is a carp, and in Japanese it is also a homophone for love — a coincidence the language has been playing on for a long time, which is part of why the fish carries the meaning it does in Japanese art.
How old is the name Koi?
Koi first appears in US birth records in 1995 — 30 years ago. The typical Koi is a kid of about 8 — this name's wave is very recent. About 800 people named Koi are estimated to be alive in the US today.
When was the name Koi most popular?
Koi peaked in 2022, reaching #2243 nationally. Today it ranks #3036, 793 places below that high. See the whole 2022 chart.
Lists built from the same records:
Where it comes from
Origin, sound and short forms
The story of Koi
Ornamental carp were bred in Japan from the nineteenth century by rice farmers in Niigata who noticed color mutations in the fish they kept in the paddies; the colored varieties are properly nishikigoi. The fish appears throughout Japanese art as a symbol of perseverance, from the story of the carp that swims up a waterfall and becomes a dragon. The homophone with love reinforced all of it. As a given name Koi is very recent and mostly American, given to sons and daughters alike.
Meaningscholars disagree
carp — and, as a homophone, love
Japanese koi written 鯉 is the carp; koi written 恋 is romantic love. They are separate words that happen to sound alike, and Japanese poetry and art have made deliberate use of the pun for centuries. Which a family means is their own business and the spelling in Roman letters cannot say. Hawaiian and other languages have their own unrelated koi.
Pronouncing Koi
KOY
One syllable, rhyming with boy. Japanese says it as two light beats, ko-i, without an English diphthong, but the American saying is close enough to pass everywhere.
Nicknames for Koi
Limited
What the data says
146 years of official birth records
The long climb, and where it stands now
The same years in position rather than babies
- First recorded
- 1995
- Most boys named
- 202264 — the highest on record
- Peak rank
- #2243reached in 2022
- Change vs 2024
- −18.4%40 in 2025, from 49
Rank is a position, a count is a headcount, and they move independently — a name can hold its rank while the number of babies behind it falls. Source: U.S. Social Security Administration.
Koi in other languages
The same name elsewhere
- 鯉 in Japanese — transliteration
- 恋 in Japanese — transliteration
Strongest US states over the last decade: Texas, Georgia, Louisiana.
Kois among us
people named Koi are estimated to be alive in the US today
About 1 boy in 42,702 born in 2025 was named Koi
Estimated from SSA birth records and published actuarial life tables. Method
Spellings of Koi
- #3036
- Koi on the 2025 chart
- #708
- counting every spelling
The SSA counts spellings, not names. Koi went to 40 boys in 2025, but Coy, Khoi and Koy and the rest below are the same name said out loud. Together the 5 spellings went to 222, which makes it the 708th most-given boys’ name of the year — 2,328 places above the chart.
About 1 boy in 7,694 born in 2025 was given one of these spellings — against 1 in 42,702 for Koi itself.
Spellings are grouped by a fixed rule that folds interchangeable English spellings of one sound (ck/k, ph/f, x/ks, a non-initial y for i) and keeps vowels apart, so Sean and Shawn stay separate names. It errs towards splitting: a family here is never larger than the truth. SSA national data, 2025. Method
Is it right for you
What happens to a name after it peaks
The Thaddius test
Every popular name lives one long story — a climb, a peak, a slow settling back. Koi's later chapters haven't been written yet, so we borrowed them: Thaddius climbed just as high around 1972, and its whole arc is on record. Line the two peaks up, and Thaddius's path sketches the road Koi is walking now.
Koi sits in the calm middle of the cycle — neither chasing a wave nor sliding off one. Middle-of-the-cycle names age slowly and predictably.
A scored estimate from 146 years of naming cycles — not a prophecy. Great names outlive statistics. How this is scored
Where Koi is headed
Koi should hold steady through 2030 — the curve is flat, and flat curves are the most predictable kind. Its history is short or jumpy, though, so read this as a sketch rather than a promise.
Low confidence — fitted on official counts through 2025.
A damped-trend projection of the official birth data — a sketch of momentum, not a promise. Every name's forecast, ranked.
Koi beside its neighbors
The names ranked closest to Koi in 2025, in babies rather than position — the bars are to scale.
US boys given each name in 2025.
The trade-off
- Three letters, one syllable, and easy for a small child to write.
- A concrete meaning with a rich and genuinely interesting body of imagery behind it.
- Used for both sexes, with no strong pull either way.
- To a Japanese speaker it is a fish or a common noun rather than a name.
- It is very short and will be assumed to be a nickname or an initial on forms.
- Koi, Coy and Koy all circulate and Coy is an ordinary English adjective.
Nobody names a baby alone.
Put Koi to the vote.
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What they receive
Someone added a name to your list
Koi
Masculine · #3036 in the U.S.
Frequently asked
- How many Kois are there in the world?
- No country counts the world's names, so there is no worldwide figure — anyone quoting one is estimating. About 800 people named Koi are estimated to be alive in the US today.
- How do you spell Koi?
- Koi is one of 5 recorded spellings. Coy is the more common one — 123 births in 2025 against 40 for Koi.
- How popular is the name Koi in 2025?
- Koi ranks #3036 among US boy names in 2025, with 40 babies given the name.
- How rare is the name Koi?
- About 1 in every 42,702 US boys born in 2025 was named Koi — 40 in all.
- Will my child share the name Koi with classmates?
- Koi will almost certainly be the only one in school.
Ranked beside Koi
Names sitting at a similar level of popularity right now.
Loren#3036 · Williams#3036 · Collier#3036 · Amadou#3036 · Kavion#3036 · Sheppard#3036 · Sailor#3036 · Claude#3036
Looking for what else is popular rather than what resembles Koi? See the current top 100.
Choosing between Koi and another name?
See them side by side — full stats, history and a gentle verdict.
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Weighing a whole shortlist? Add the rest in the builder, or settle it with a bracket.
Cast your vote
Which one would you pick?
Your gut first, the numbers after — the split shows once you pick.
US figures from the Social Security Administration. 1880–2025. Data & methodology
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