2000
#7,178
National surname rank
Recorded bearers 4,286
First available Census row
Per 100,000 1.59
Uncommon Last name
Cai
A Chinese surname meaning "colorful" or "vegetable," or an Italian surname referring to an abbreviation of the given name Gaius.
According to the 2020 US Census Bureau surname tables, roughly 15,224 Americans carry the last name Cai. That puts it at #2,651 in the national surname ranking, appearing at a frequency of 4.44 per 100,000 people (about 1 in 22,514 residents).
This page is the full Name Census profile for the Cai 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.
For British records, Name Census UK has a British surname profile for Cai with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
15K
1 in 22,514
Census rank
#2,651
2020 decennial data
Per 100,000
4.4
Frequency rate
Recorded bearers
13K
uncommon in the US
Popularity narrative
The Census Bureau recorded 13,276 bearers of the surname Cai in its 2020 decennial surname file. At a rate of 4.44 per 100,000 residents, it holds the 2651st position in the national surname ranking.
Among Census respondents with the surname Cai, the largest self-reported group is Asian/Pacific Islander at 95.9%. The next largest groups are White (2.6%) and Two or More Races (0.7%).
Origin
Meaning and origin of Cai
The surname CAI originated in China, with the earliest records dating back to the Tang Dynasty (618-907 AD). It is derived from the Chinese word "cai," which means wealth or fortune. The name was initially associated with people who were prosperous or had achieved financial success.
During the Song Dynasty (960-1279 AD), the CAI surname gained prominence and was widely adopted by families across various regions of China. Historical records from this period, such as the Song Huiyao (a collection of government documents), mention individuals bearing the surname CAI.
One notable figure bearing this surname was Cai Xiang (1012-1067 AD), a prominent scholar and statesman during the Song Dynasty. He served as a high-ranking official and was known for his contributions to Neo-Confucian philosophy.
In the Ming Dynasty (1368-1644 AD), the surname CAI continued to be prevalent, particularly in the eastern provinces of Zhejiang and Jiangsu. The "Cai" place name can be found in various locations within these regions, suggesting that the surname may have originated or been concentrated in these areas.
Another significant figure with the CAI surname was Cai Lun (63-121 AD), a renowned inventor and official during the Eastern Han Dynasty. He is credited with the invention of paper, a significant contribution that had a profound impact on the spread of knowledge and communication in ancient China.
During the Qing Dynasty (1644-1912 AD), the CAI surname was widely dispersed throughout China, with notable individuals such as Cai Yuanpei (1868-1940), a prominent educator and politician who played a crucial role in modernizing China's education system.
Other notable individuals with the CAI surname include Cai Yuanpei (1868-1940), an influential educator and politician during the late Qing and early Republican era, and Cai Qing (1858-1935), a renowned painter and calligrapher of the late Qing Dynasty.
It is important to note that historical records and documentation may have variations in the spelling or romanization of the surname CAI due to the complexities of transliterating Chinese characters into different writing systems over time.
Demographics
Ancestry and ethnicity for Cai
Among Census respondents with the surname Cai, the largest self-reported group is Asian/Pacific Islander at 95.9%. The next largest groups are White (2.6%) and Two or More Races (0.7%).
The bar chart below shows how Cai 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 Cai surname at the time of the 2020 Census, not any inherent property of the name itself.
- Asian and Pacific Islander95.9% · 12,734
- White2.6% · 342
- Two or more races0.7% · 90
- Black or African American0.5% · 70
- Hispanic or Latino0.3% · 40
Timeline
Historical Census data for Cai
Cai 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
#4,191
National surname rank
Recorded bearers 8,457
+4,171 bearers (+97.3%)
Per 100,000 2.87
Rank movement Up 2,987 places
2020
#2,651
National surname rank
Recorded bearers 13,276
+4,819 bearers (+57.0%)
Per 100,000 4.44
Rank movement Up 1,540 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #7,178 | 4,286 | 1.59 | First available Census row | First available Census row |
| 2010 | #4,191 | 8,457 | 2.87 | +4,171 bearers (+97.3%) | Up 2,987 places |
| 2020 | #2,651 | 13,276 | 4.44 | +4,819 bearers (+57.0%) | Up 1,540 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 Cai 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 | #4,191 | #2,651 | 36.7% |
| Count | 8,457 | 13,276 | 57.0% |
| Per 100K | 2.87 | 4.44 | 54.8% |
Between the 2010 and 2020 Census, the number of Cai bearers went from 8,457 to 13,276 (+57.0% change). The surname moved up 1,540 positions in the national ranking, going from #4,191 to #2,651.
FAQ
Cai surname: questions and answers
How many people in the U.S. have the surname Cai?
Name Census estimates that about 15,224 living Americans carry the surname Cai. Using the current population baseline, that works out to roughly 1 in 22,514 residents.
How common is Cai?
Cai ranks #2,651 in the 2020 Census surname tables and is classified on this site as "Uncommon." The Census recorded the name at a frequency of 4.44 per 100,000 residents, which is about 4 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 13,276 people with the surname Cai. That is different from the site's living-bearer estimate (15,224), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 4.44 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 4.44 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 4 of them to have the surname Cai.
Has Cai become more or less common over time?
Between 2010 and 2020, the surname Cai went from 8,457 recorded bearers to 13,276. That is an increase of 4,819 (+57.0%). In the national ranking it rose from #4,191 to #2,651.
What does the Census say about the background of Cai?
Among Census respondents with the surname Cai, the largest self-reported group is Asian/Pacific Islander at 95.9%. The next largest groups are White (2.6%) and Two or More Races (0.7%). 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 Cai in the 2020 Census, accounting for 95.9% (12,734 people in the source table).
What is the full ancestry breakdown?
Cai appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are Asian/Pacific Islander (95.9%), White (2.6%), Two or More Races (0.7%). 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 Cai (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 Cai mean?
A Chinese surname meaning "colorful" or "vegetable," or an Italian surname referring to an abbreviation of the given name Gaius. 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 Cai (4.44 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 have the last name Cai?
Find out how many people are called Cai on our sister site HowManyOfMe.org — a quick modern estimate with the living-bearer count front and centre.