How Many People Are Named Obrien?
An estimated 198 people in the United States have the first name Obrien. It is almost exclusively a male name. The average bearer is 31 years old, and Obrien peaked in popularity in 1991 with 16 births that year.
Below you will find a full statistical profile of Obrien as a first name in the United States, including gender data, a year-by-year popularity timeline going back to 1880, a decade breakdown, and state-by-state birth registrations. You can also check how many people share the full name Obrien paired with any surname.
Estimated Living Americans
198
About 1 in 1,731,083 people in the U.S.
Rarity
Very Rare
Predicted Gender
Male
100.0% confidence
Average Age
31
years old
Peak Year
1991
16 births
Total Registered
209
since 1880
Gender Distribution for Obrien
Obrien is almost exclusively a male name. Out of 209 total births registered, 100.0% were male.
Obrien as a male name
Ranked #10,558 in 2022
7 male births in 2022
Peak: 1991 (16 births)
Obrien: Popularity Over Time
SSA records for Obrien span from the 1920s to the 2020s, covering 8 decades of naming data. The most popular decade for this name was the 1980s, when 66 babies were registered. Obrien has declined significantly from its peak in the 1980s. Recent registrations are a fraction of what they were at the name's height.
Obrien by Decade
How has Obrien tracked across different eras? The table below groups all SSA birth registrations into 10-year periods, with separate male and female counts. The colored bar shows each decade's share relative to the peak.
Obrien + Last Name Combinations
How many people share a full name with Obrien as the first name? Click a combination below to see the estimate, or search any pairing.
Names Similar to Obrien
Other first names starting with O with a similar number of bearers.
Obrien: Questions and Answers
How many people in the U.S. are named Obrien?
We estimate approximately 198 people named Obrien are alive in the United States today. This is based on SSA birth records from 1880 to 2024, adjusted for mortality using CDC life tables. About 1 in 1,731,083 Americans share this first name.
Is Obrien a common name?
Obrien is classified as "Very Rare" and is more popular than 74.1% of all first names in the SSA database. A total of 209 births have been registered with this name since 1880.
When was Obrien most popular?
Obrien reached peak popularity in 1991, when 16 babies were given this name. The average age of a living person named Obrien is approximately 31 years old, reflecting when the name was most commonly given.
Is Obrien a male name?
Obrien is predominantly male. 100.0% of people with this name are male. See the gender breakdown above for full details.
How many Obrien Smiths are there?
To find how many people share a specific full name, we combine first name and surname frequencies. Try: Obrien Smith, Obrien Johnson, Obrien Williams. You can also search any combination on our homepage.
Where does this data come from?
Our estimates use Social Security Administration birth records (1880 to 2024), adjusted for survival using CDC 2023 life tables broken down by sex. The U.S. population figure (342,754,338) is from the Census Bureau's July 2025 estimate. Full methodology.
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