2000
#150,436
National surname rank
Recorded bearers 100
First available Census row
Per 100,000 0.04
Very Rare Last name
Tomooka
A Japanese surname meaning "rice paddy ridge".
According to the 2020 US Census Bureau surname tables, roughly 125 Americans carry the last name Tomooka. That puts it at #150,205 in the national surname ranking, appearing at a frequency of 0.04 per 100,000 people (about 1 in 2,742,035 residents).
This page is the full Name Census profile for the Tomooka surname. You will find the Census Bureau frequency data, a multi-census history view, an ancestry and ethnicity breakdown based on self-reported demographics, the name's meaning and origin where available, and answers to the most common questions people ask about this surname.
Bearers in the US
125
1 in 2,742,035
Census rank
#150,205
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
109
very rare in the US
Popularity narrative
The Census Bureau recorded 109 bearers of the surname Tomooka in its 2020 decennial surname file. At a rate of 0.04 per 100,000 residents, it holds the 150205th position in the national surname ranking.
Among Census respondents with the surname Tomooka, the largest self-reported group is Asian/Pacific Islander at 56.9%. The next largest groups are Two or More Races (22.0%) and White (13.8%).
Origin
Meaning and origin of Tomooka
The surname "TOMOOKA" is of Japanese origin, tracing its roots back to the medieval period in Japan. It is believed to have derived from a combination of two Japanese words, "tomo" meaning friend or companion, and "oka" referring to a hill or small mountain.
The name is thought to have originated in the rural areas of Japan, particularly in the mountainous regions, where families may have lived near or on small hills or elevated areas. This geographical connection could have led to the surname being adopted as a way to identify individuals and their place of residence.
While there are no definitive historical records or manuscripts that explicitly mention the surname "TOMOOKA," it is likely that the name has been in existence for several centuries. Japanese family names have a long history, with many surnames dating back to the Kamakura period (1185-1333) or even earlier.
One of the earliest recorded individuals with the surname "TOMOOKA" was Tomooka Masahiro, a samurai warrior who lived in the late 16th century during the Sengoku period. He was known for his bravery and loyalty to his lord, and his name is mentioned in several historical accounts of the time.
Another notable figure was Tomooka Shozo (1848-1919), a Japanese politician and diplomat who served as the Minister of Foreign Affairs in the early 20th century. He played a significant role in shaping Japan's foreign policy during a crucial period of modernization and international relations.
In the realm of literature, Tomooka Aya (1901-1945) was a prominent Japanese novelist and poet. Her works often explored themes of love, loss, and the complexities of human relationships. She is considered one of the most influential writers of the early 20th century in Japan.
Tomooka Hiroshi (1925-2012) was a renowned Japanese architect, known for his innovative designs and contributions to the field of sustainable architecture. His works included residential and commercial buildings, as well as public spaces and urban planning projects.
Lastly, Tomooka Naoko (born 1963) is a contemporary Japanese artist and sculptor. Her installations and sculptures explore themes of identity, memory, and the human condition, often incorporating traditional Japanese materials and techniques.
While the surname "TOMOOKA" may have evolved over time, with slight variations in spelling or pronunciation, its roots can be traced back to the historical and cultural context of Japan, reflecting the rich tapestry of the country's past.
Demographics
Ancestry and ethnicity for Tomooka
Among Census respondents with the surname Tomooka, the largest self-reported group is Asian/Pacific Islander at 56.9%. The next largest groups are Two or More Races (22.0%) and White (13.8%).
The bar chart below shows how Tomooka bearers described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given surname, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown for every Census year so the breakdown stays comparable over time. When the source file also includes raw headcounts, Name Census shows those alongside the percentages in the legend.
Keep in mind that these are self-reported numbers. A person's surname does not determine their race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the Tomooka surname at the time of the 2020 Census, not any inherent property of the name itself.
- Asian and Pacific Islander56.9% · 62
- Two or more races22.0% · 24
- White13.8% · 15
- Hispanic or Latino4.6% · 5
- American Indian and Alaska Native1.8% · 2
- Black or African American0.9% · 1
Timeline
Historical Census data for Tomooka
Tomooka appears in 3 published Census surname files: 2000, 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2010
#148,347
National surname rank
Recorded bearers 111
+11 bearers (+11.0%)
Per 100,000 0.04
Rank movement Up 2,089 places
2020
#150,205
National surname rank
Recorded bearers 109
-2 bearers (-1.8%)
Per 100,000 0.04
Rank movement Down 1,858 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #150,436 | 100 | 0.04 | First available Census row | First available Census row |
| 2010 | #148,347 | 111 | 0.04 | +11 bearers (+11.0%) | Up 2,089 places |
| 2020 | #150,205 | 109 | 0.04 | -2 bearers (-1.8%) | Down 1,858 places |
For 2020, the Census Bureau published race and Hispanic-origin columns as counts rather than percentages. Name Census converts those counts back into shares so the ancestry section stays comparable with the older surname files.
Year on year
2010 vs 2020 Census
How has the Tomooka surname changed between Census years? The chart shows bearer count side by side, and the table compares rank, count, and frequency.
Census year comparison
20102020
| Metric | 2010 | 2020 | Change |
|---|---|---|---|
| Rank | #148,347 | #150,205 | -1.3% |
| Count | 111 | 109 | -1.8% |
| Per 100K | 0.04 | 0.04 | -8.8% |
Between the 2010 and 2020 Census, the number of Tomooka bearers went from 111 to 109 (-1.8% change). The surname moved down 1,858 positions in the national ranking, going from #148,347 to #150,205.
FAQ
Tomooka surname: questions and answers
How many people in the U.S. have the surname Tomooka?
Name Census estimates that about 125 living Americans carry the surname Tomooka. Using the current population baseline, that works out to roughly 1 in 2,742,035 residents.
How common is Tomooka?
Tomooka ranks #150,205 in the 2020 Census surname tables and is classified on this site as "Very Rare." The Census recorded the name at a frequency of 0.04 per 100,000 residents, which is about 0 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 109 people with the surname Tomooka. That is different from the site's living-bearer estimate (125), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 0.04 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 0.04 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 0 of them to have the surname Tomooka.
Has Tomooka become more or less common over time?
Between 2010 and 2020, the surname Tomooka went from 111 recorded bearers to 109. That is a decrease of 2 (-1.8%). In the national ranking it fell from #148,347 to #150,205.
What does the Census say about the background of Tomooka?
Among Census respondents with the surname Tomooka, the largest self-reported group is Asian/Pacific Islander at 56.9%. The next largest groups are Two or More Races (22.0%) and White (13.8%). These figures come from the 2020 Census Bureau surname tables, based on how respondents described their own race and ethnicity.
Which group reports this surname most often?
Asian/Pacific Islander is the largest self-reported group for the surname Tomooka in the 2020 Census, accounting for 56.9% (62 people in the source table).
What is the full ancestry breakdown?
Tomooka appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Asian/Pacific Islander (56.9%), Two or More Races (22.0%), White (13.8%). For 2020, the source file also published raw headcounts for each group, which is why this page can show both percentages and counts in the ancestry section.
Is this page using the latest Census data?
Yes. This page is using the latest surname file currently loaded on Name Census, which is 2020. The historical section above also keeps any older Census surname entries we have for Tomooka (2000, 2010, 2020).
Does the Census include every surname?
No. The Census Bureau only publishes surnames that appeared at least 100 times in a given decennial Census. That means very rare surnames are excluded entirely, and a surname can appear in one Census release but disappear from a later one if it falls below the reporting threshold.
Why don't the ancestry percentages always add up to exactly 100%?
There are two main reasons: rounding and suppression. The Census Bureau rounds published values, and it may suppress very small cells to protect privacy. For 2020, the Bureau also published raw group counts rather than direct percentages, so Name Census converts those counts back into shares for comparability across census years.
What does Tomooka mean?
A Japanese surname meaning "rice paddy ridge". The fuller origin note on this page goes into more detail.
Where does the surname data come from?
All surname statistics on Name Census are drawn from the US Census Bureau's decennial surname frequency tables. These files list every surname that appeared 100 or more times in the 2020 Census, along with a count, a per-100,000 rate, and a self-reported demographic breakdown. You can read the full explanation on our methodology page.
How does Name Census estimate living bearers?
For surnames, Name Census does not age cohorts the way it does for first names. Instead, it takes the Census Bureau's published frequency for Tomooka (0.04 per 100,000) and applies that rate to the current U.S. resident population to estimate how many living Americans have the surname today.
How many Americans have the surname Tomooka?
For a faster, more casual read, check HowManyOfMe.org — our sister site built around that single question.