Seiji
A masculine Japanese name meaning "accomplished" or "composed".
Name Census estimates that about 398 living Americans carry the first name Seiji. The name is used almost exclusively for boys. The average person named Seiji today is around 24 years old, and the year with the single highest number of Seiji births was 2007 (19 babies).
This page is the full Name Census profile for Seiji. 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
398
~ 1 in 861,192 Americans
Peak year
2007
19 babies that year
Average age
24
years old
2024 SSA rank
#9,694
Tracked since 1914
Popularity
Seiji: popularity over time
The SSA tracks Seiji from the 1910s through to the 2020s, spanning 9 decades of birth certificate data. The biggest single decade for the name was the 2000s, with 116 total registrations. Although the numbers have come down from the 2000s peak, Seiji remains solidly in use and shows no sign of disappearing from maternity wards.
Babies born per year
Decades
Seiji 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 Seiji during that decade, along with a combined total. This is useful for spotting eras where the name surged or retreated.
Geography
Where Seijis live
Origin
Meaning and history of Seiji
The given name Seiji has its origins in Japan, where it has been used for centuries. The name is composed of two Japanese kanji characters: "sei" meaning "truth" or "sincerity," and "ji" meaning "child" or "son." Together, the name Seiji can be interpreted as "sincere child" or "truthful son."
In ancient Japan, the name Seiji was often given to boys as a symbolic wish for them to grow up with honesty and integrity. It was a popular choice among samurai families and the nobility, who placed great importance on values such as honor and truthfulness.
One of the earliest recorded bearers of the name Seiji was Seiji Tōgō (1836-1919), a prominent Japanese admiral who played a crucial role in the Russo-Japanese War of 1904-1905. His decisive victory at the Battle of Tsushima is considered one of the greatest naval battles in modern history.
Another notable figure in Japanese history with the name Seiji was Seiji Nagai (1886-1951), a Christian philosopher and author who survived the atomic bombing of Nagasaki in 1945. His book "The Bells of Nagasaki" recounts his experiences during the bombing and his efforts to help the survivors.
In the realm of literature, Seiji Tsutsumi (1927-1991) was a renowned Japanese novelist and playwright. His works often explored themes of social injustice and human resilience. He received numerous literary awards, including the Akutagawa Prize and the Naoki Prize.
The name Seiji has also been borne by influential figures in Japanese politics and business. Seiji Ozawa (born 1935) is a celebrated conductor and former music director of the Boston Symphony Orchestra. His contributions to classical music have earned him numerous accolades, including a Grammy Award.
Another notable bearer of the name was Seiji Natsume (1923-2005), a Japanese businessman who served as the chairman and CEO of Sony Corporation. Under his leadership, Sony became a global electronics powerhouse and a symbol of Japanese innovation and technological prowess.
While the name Seiji has its roots in Japan, it has also gained popularity in other parts of the world, particularly among individuals with Japanese ancestry or those with an appreciation for Japanese culture and values.
People
Seiji + last name combinations
How many people share a full name with Seiji as the first name? Click a combination below to see the estimate, or search any pairing.
Related
Other names starting with S
Other first names starting with S with a similar number of bearers.
FAQ
Seiji: questions and answers
How many people in the U.S. are named Seiji?
Name Census puts the figure at roughly 398 living Americans. We arrive at this by taking every SSA birth registration for Seiji 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 861,192 US residents.
Is Seiji a common name?
We classify Seiji as "Very Rare". It ranks above 82.3% of all first names in the SSA dataset by living bearers. Across the full history of the data, 509 babies have been registered with this name.
When was Seiji most popular?
The single biggest year for Seiji was 2007, when 19 babies received the name. The fact that the average living Seiji is about 24 years old gives you a rough sense of which era contributed the most bearers who are still alive today.
Is Seiji a male name?
Yes, 100.0% of people registered as Seiji 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.
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.