William Clay
There are approximately 387 people named William Clay living in the United States today. That makes this name combination very rare, occurring at a rate of about 1 in 885,670 Americans.
This estimate combines SSA birth records for the first name William with Census Bureau frequency data for the surname Clay. Below you will find a breakdown of both names, including popularity trends, gender data, and ancestry information.
Expected bearers
387
1 in 885,670
Named William
2.3M
Alive today
Named Clay
57K
Alive today
US population
343M
Denominator
Estimated living: 2.3M
Rarity: Very Common
Gender: Male
Peak year: 1947
Average age: 54
Estimated bearers: 57K
Rarity: Uncommon
Census rank: #708
Per 100K: 16.56
Top ancestry: White (52.7%)
First name trend
William: popularity over time
Year-by-year SSA birth registrations for the first name William. The peak year was 1947 with 67,155 births. The average person named William today is 54 years old.
Babies born per year
Ethnicity
Ancestry of the Clay surname
Self-reported race and ethnicity breakdown for people with the surname Clay, from the 2010 US Census Bureau. The largest group is White at 52.7%.
- White52.7%
- Black or African American40.5%
- Two or more races2.9%
- Hispanic or Latino2.4%
- American Indian and Alaska Native0.9%
- Asian and Pacific Islander0.5%
Methodology
How we calculated this
The first name William has a living-bearer frequency of 0.6813% of the US population, based on 2,335,115 estimated living Americans carrying this first name (from SSA birth records going back to 1880, adjusted for mortality using CDC life tables).
The surname Clay appears at a rate of 16.56 per 100,000 residents in the 2010 Census Bureau surname file, which translates to a frequency of 0.0166%.
Multiplying these two independent frequencies against the current US population of 342,754,338 gives an expected count of approximately 387 people with the full name William Clay. This assumes statistical independence between first and last names, which is a simplification but produces reasonable estimates for most combinations.
Related
Other people named William
Related
Other people with the surname Clay
FAQ
William Clay: questions and answers
How many people are named William Clay?
We estimate approximately 387 people in the United States share the full name William Clay. That works out to about 1 in 885,670 Americans. This is calculated by combining the first-name frequency (0.6813%) with the surname frequency (16.56 per 100K) against the current US population.
How rare is the name William Clay?
We classify William Clay as "Very Rare". About 1 in 885,670 Americans share this exact first and last name combination.
Is William a male or female name?
William is predominantly male. Out of 4,205,026 total SSA registrations, 99.6% were male and 0.4% were female. See the full William profile for detailed gender data.
Where does this data come from?
First-name data comes from the Social Security Administration's national baby name files (1880 to 2024). Surname data comes from the 2010 US Census Bureau decennial surname tables. Living-bearer estimates use CDC actuarial life tables to adjust for mortality. Read the full methodology.