2000
#143,847
National surname rank
Recorded bearers 106
First available Census row
Per 100,000 0.04
Very Rare Last name
Klementowski
A Polish surname derived from the name Klement, meaning "merciful" or "compassionate."
According to the 2020 US Census Bureau surname tables, roughly 127 Americans carry the last name Klementowski. That puts it at #148,665 in the national surname ranking, appearing at a frequency of 0.04 per 100,000 people (about 1 in 2,698,853 residents).
This page is the full Name Census profile for the Klementowski 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
127
1 in 2,698,853
Census rank
#148,665
2020 decennial data
Per 100,000
0.0
Frequency rate
Recorded bearers
111
very rare in the US
Popularity narrative
The Census Bureau recorded 111 bearers of the surname Klementowski in its 2020 decennial surname file. At a rate of 0.04 per 100,000 residents, it holds the 148665th position in the national surname ranking.
Among Census respondents with the surname Klementowski, the largest self-reported group is White at 91.9%. The next largest groups are Hispanic (4.5%) and Two or More Races (1.8%).
Origin
Meaning and origin of Klementowski
The surname Klementowski is of Polish origin, with its roots traced back to the Middle Ages. It is a locative name, derived from the Polish town of Klementy or a similar place name. The suffix "-owski" indicates a connection to a specific locality.
Klementowski is believed to have originated from the personal name Klemens, which itself derives from the Latin name Clemens, meaning "merciful" or "mild." This personal name was widespread in medieval Poland, as it was a popular saint's name.
One of the earliest recorded instances of the surname Klementowski can be found in the famous Metryka Koronna, a collection of Crown Metrica records from the 15th to the 18th century, which documented various administrative and legal matters in the Polish-Lithuanian Commonwealth.
In the 16th century, a notable bearer of the name was Jan Klementowski (c. 1510-1580), a Polish nobleman and military commander who participated in several battles against the Teutonic Knights and the Crimean Khanate.
Another prominent figure was Franciszek Klementowski (1608-1668), a Polish-Lithuanian nobleman and politician who served as the Grand Treasurer of the Crown from 1661 to 1668.
The 17th century saw the rise of Stanisław Klementowski (1635-1698), a Polish Jesuit priest and writer who authored several religious texts and treatises.
In the 18th century, Marcin Klementowski (1720-1795) was a prominent Polish painter and portraitist, known for his works depicting the Polish nobility and gentry.
Moving into the 19th century, Józef Klementowski (1805-1882) was a Polish lawyer and politician who served as a member of the Prussian House of Representatives and advocated for Polish national rights.
Throughout its history, the surname Klementowski has been associated with various noble families and notable individuals in Poland, reflecting its significance and longevity within Polish culture and society.
Demographics
Ancestry and ethnicity for Klementowski
Among Census respondents with the surname Klementowski, the largest self-reported group is White at 91.9%. The next largest groups are Hispanic (4.5%) and Two or More Races (1.8%).
The bar chart below shows how Klementowski 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 Klementowski surname at the time of the 2020 Census, not any inherent property of the name itself.
- White91.9% · 102
- Hispanic or Latino4.5% · 5
- Two or more races1.8% · 2
- Asian and Pacific Islander0.9% · 1
- American Indian and Alaska Native0.9% · 1
Timeline
Historical Census data for Klementowski
Klementowski 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
#144,141
National surname rank
Recorded bearers 115
+9 bearers (+8.5%)
Per 100,000 0.04
Rank movement Down 294 places
2020
#148,665
National surname rank
Recorded bearers 111
-4 bearers (-3.5%)
Per 100,000 0.04
Rank movement Down 4,524 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #143,847 | 106 | 0.04 | First available Census row | First available Census row |
| 2010 | #144,141 | 115 | 0.04 | +9 bearers (+8.5%) | Down 294 places |
| 2020 | #148,665 | 111 | 0.04 | -4 bearers (-3.5%) | Down 4,524 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 Klementowski 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 | #144,141 | #148,665 | -3.1% |
| Count | 115 | 111 | -3.5% |
| Per 100K | 0.04 | 0.04 | -7.2% |
Between the 2010 and 2020 Census, the number of Klementowski bearers went from 115 to 111 (-3.5% change). The surname moved down 4,524 positions in the national ranking, going from #144,141 to #148,665.
FAQ
Klementowski surname: questions and answers
How many people in the U.S. have the surname Klementowski?
Name Census estimates that about 127 living Americans carry the surname Klementowski. Using the current population baseline, that works out to roughly 1 in 2,698,853 residents.
How common is Klementowski?
Klementowski ranks #148,665 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 111 people with the surname Klementowski. That is different from the site's living-bearer estimate (127), 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 Klementowski.
Has Klementowski become more or less common over time?
Between 2010 and 2020, the surname Klementowski went from 115 recorded bearers to 111. That is a decrease of 4 (-3.5%). In the national ranking it fell from #144,141 to #148,665.
What does the Census say about the background of Klementowski?
Among Census respondents with the surname Klementowski, the largest self-reported group is White at 91.9%. The next largest groups are Hispanic (4.5%) and Two or More Races (1.8%). 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?
White is the largest self-reported group for the surname Klementowski in the 2020 Census, accounting for 91.9% (102 people in the source table).
What is the full ancestry breakdown?
Klementowski appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (91.9%), Hispanic (4.5%), Two or More Races (1.8%). 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 Klementowski (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 Klementowski mean?
A Polish surname derived from the name Klement, meaning "merciful" or "compassionate." 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 Klementowski (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 people are called Klementowski?
Want to know how many people are called Klementowski? HowManyOfMe.org, our sister site, puts the living-bearer count front and centre.