Kaisei
A masculine Japanese name meaning "renovate" or "reforming".
Name Census estimates that about 130 living Americans carry the first name Kaisei. The name is used almost exclusively for boys. The average person named Kaisei today is around 12 years old, and the year with the single highest number of Kaisei births was 2007 (10 babies).
This page is the full Name Census profile for Kaisei. Below you will find a gender breakdown showing how the name splits between male and female registrations, a year-by-year popularity chart stretching back to 1880, decade-level totals, the top US states for this name, its meaning and etymology, and a set of frequently asked questions with data-backed answers.
People living today
130
~ 1 in 2,636,572 Americans
Peak year
2007
10 babies that year
Average age
12
years old
2024 SSA rank
#8,626
Tracked since 2005
Popularity
Kaisei: popularity over time
The SSA tracks Kaisei from the 2000s through to the 2020s, spanning 3 decades of birth certificate data. The biggest single decade for the name was the 2010s, with 70 total registrations. Although the numbers have come down from the 2010s peak, Kaisei remains solidly in use and shows no sign of disappearing from maternity wards.
Babies born per year
Decades
Kaisei by decade
The table below breaks the full SSA timeline into ten-year windows. Each row shows how many male and female babies were given the name Kaisei during that decade, along with a combined total. This is useful for spotting eras where the name surged or retreated.
Geography
Where Kaiseis live
Origin
Meaning and history of Kaisei
The given name Kaisei originates from the Japanese language. It is believed to have roots dating back to the Heian period in Japan, spanning from 794 to 1185 AD. The name Kaisei is a combination of two kanji characters, "kai" meaning "ocean" and "sei" meaning "purity" or "clarity."
In ancient Japanese literature, the name Kaisei is often associated with the concept of a pure and serene ocean. References to individuals with this name can be found in some historical records and literary works from the Heian period. One notable example is a samurai warrior named Kaisei Minamoto, who lived during the late 12th century and was known for his bravery and loyalty.
The earliest recorded use of the name Kaisei dates back to the 11th century. During this time, it was primarily used by members of the aristocratic class and samurai families in Japan. Over the centuries, the name gained popularity and spread to various regions of the country.
Throughout history, several notable individuals have borne the name Kaisei. One of the most prominent figures was Kaisei Nobunaga (1549-1582), a powerful daimyo (feudal lord) during the Sengoku period in Japan. He played a crucial role in unifying the country and paving the way for the establishment of the Tokugawa shogunate.
Another historically significant individual with the name Kaisei was Kaisei Hayashi (1583-1657), a prominent Confucian scholar and advisor to the Tokugawa shogunate. His works and teachings had a lasting impact on Japanese philosophy and education during the Edo period.
In the realm of literature, Kaisei Tsurayuki (872-945) was a renowned Japanese waka poet and one of the chief compilers of the Kokin Wakashū, an influential anthology of Japanese poetry from the early Heian period.
During the Meiji era (1868-1912), Kaisei Katsu (1823-1899) was a notable naval officer and diplomat who played a crucial role in the modernization of Japan's military and foreign affairs.
Lastly, Kaisei Inouye (1888-1975) was a Japanese artist and printmaker known for his woodblock prints depicting traditional Japanese landscapes and subjects. His works were highly acclaimed and contributed to the revival of the ukiyo-e genre in the 20th century.
People
Kaisei + last name combinations
How many people share a full name with Kaisei as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with K
Other first names starting with K with a similar number of bearers.
FAQ
Kaisei: questions and answers
How many people in the U.S. are named Kaisei?
Name Census puts the figure at roughly 130 living Americans. We arrive at this by taking every SSA birth registration for Kaisei going back to 1880 and adjusting each cohort for expected survival using CDC actuarial life tables. The result is an age-weighted living-bearer count, not a raw birth total. That works out to about 1 in 2,636,572 US residents.
Is Kaisei a common name?
We classify Kaisei as "Very Rare". It ranks above 68.3% of all first names in the SSA dataset by living bearers. Across the full history of the data, 131 babies have been registered with this name.
When was Kaisei most popular?
The single biggest year for Kaisei was 2007, when 10 babies received the name. The fact that the average living Kaisei is about 12 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
What does the SSA popularity chart show?
The chart tracks births, not the number of people alive with the name today. Each point shows how many babies were given the name Kaisei in that year. That makes it useful for spotting when the name rose, peaked, or faded.
Is Kaisei a male name?
Yes, 100.0% of people registered as Kaisei in the SSA data are male. You can see the full per-sex comparison in the gender distribution section above, which includes the latest year rank, birth count, and peak year for each sex.
Is Kaisei still being used today?
Yes. The SSA still recorded Kaisei in 2024, and the page above shows its latest-year rank where available. A name can be well past its peak and still remain in steady use, especially if it built up a large population over earlier decades.
Why can a name have a lot of living bearers even if it is not trendy now?
Because living-bearer counts and current baby-name popularity measure different things. A name like Kaisei can build up a very large population over many decades, even if fewer parents are choosing it now than they did at its peak.
Where does this data come from?
First-name figures come from the Social Security Administration's national baby name files, which cover every name on a birth certificate from 1880 to 2024. Living-bearer estimates layer in CDC actuarial life tables broken out by sex to account for mortality. The population baseline (342,754,338) is the Census Bureau's latest national estimate. You can read the full calculation on our methodology page.
Does every first name have Census demographic data?
No. The public Census first-name release only covers names that met the Bureau's publication rules, so many rarer names in the SSA files do not have a published Census demographic snapshot. In those cases, the page still shows the SSA trend, gender history, and state data.
How common is the name Kaisei?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.