Katharine Isabelle
There are approximately 1 people named Katharine Isabelle living in the United States today. That makes this name combination very rare, occurring at a rate of about 1 in 342,754,338 Americans.
This estimate combines SSA birth records for the first name Katharine with Census Bureau frequency data for the surname Isabelle. Below you will find a breakdown of both names, including popularity trends, gender data, and Census demographics where available.
Expected bearers
1
1 in 342,754,338
Named Katharine
27K
Alive today
Named Isabelle
1.2K
Alive today
US population
343M
Denominator
Estimated living: 27K
Rarity: Uncommon
Gender: Female
Peak year: 1982
Average age: 45
Top Census group: White (89.8%)
Estimated bearers: 1.2K
Rarity: Rare
Census rank: #25,489
Per 100K: 0.34
Top ancestry: White (72.0%)
First name trend
Katharine: popularity over time
Year-by-year SSA birth registrations for the first name Katharine. The peak year was 1982 with 947 births. The average person named Katharine today is 45 years old.
Babies born per year
Demographics
Ancestry and ethnicity for Katharine
Self-reported race and ethnicity breakdown for people with the first name Katharine, from the 2020 US Census Bureau first-name tables. The largest published group is White at 89.8%.
The bar chart below shows how people with the first name Katharine described their own race and ethnicity on the 2020 Census form. These are self-reported numbers, and they describe the population who happened to carry the name Katharine at the time of the Census. A first name does not determine a person's race or ethnicity.
- White89.8% · 26,373
- Hispanic or Latino4.0% · 1,161
- Two or more races2.8% · 836
- Asian and Pacific Islander2.1% · 604
- Black or African American1.1% · 331
- American Indian and Alaska Native0.2% · 64
Ethnicity
Ancestry of the Isabelle surname
Self-reported race and ethnicity breakdown for people with the surname Isabelle, from the 2020 US Census Bureau. The largest group is White at 72.0%.
The bar chart below shows how people with the surname Isabelle described their own race and ethnicity on the 2020 Census form. These are self-reported numbers, and they describe the population who happened to carry the surname Isabelle at the time of the Census. A surname does not determine a person's race or ethnicity.
- White72.0% · 732
- Black or African American18.6% · 189
- Hispanic or Latino6.0% · 61
- Two or more races2.2% · 22
- Asian and Pacific Islander1.1% · 11
- American Indian and Alaska Native0.1% · 1
Methodology
How we calculated this
The first name Katharine has a living-bearer frequency of 0.0078% of the US population, based on 26,798 estimated living Americans carrying this first name (from SSA birth records going back to 1880, adjusted for mortality using CDC life tables).
Even though the Census Bureau now publishes first-name tables, we do not use that file as the main first-name input for this estimate. The latest first-name Census snapshot is from 2020, which makes it 6 years old today. Because Census first-name data is only released once every 10 years, SSA birth records plus CDC survival rates give a better current estimate of how many people are likely alive with the name Katharine right now.
The surname Isabelle appears at a rate of 0.34 per 100,000 residents in the 2020 Census Bureau surname file, which translates to a frequency of 0.0003%.
Multiplying these two independent frequencies against the current US population of 342,754,338 gives an expected count of approximately 1 people with the full name Katharine Isabelle. This assumes statistical independence between first and last names, which is a simplification but produces reasonable estimates for most combinations.
Related
Other people named Katharine
FAQ
Katharine Isabelle: questions and answers
How many people are named Katharine Isabelle?
We estimate approximately 1 people in the United States share the full name Katharine Isabelle. That works out to about 1 in 342,754,338 Americans. This is calculated by combining the first-name frequency (0.0078%) with the surname frequency (0.34 per 100K) against the current US population.
How rare is the name Katharine Isabelle?
We classify Katharine Isabelle as "Very Rare". About 1 in 342,754,338 Americans share this exact first and last name combination.
Is Katharine a male or female name?
Katharine is predominantly female. Out of 41,215 total SSA registrations, 0.0% were male and 100.0% were female. See the full Katharine 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 2020 US Census Bureau decennial surname tables. Living-bearer estimates use CDC actuarial life tables to adjust for mortality. Read the full methodology.
How common is the name Katharine Isabelle?
Want to know how common the name Katharine Isabelle is? HowManyOfMe.org, our sister site, puts the living-bearer count front and centre.