Name Explorer — Baby Names
The Name O'brien
How many South Africans are called O'brien, which surnames go with it, and how old they are.
Boys and Girls Named O'brien
We make use of verified data and algorithms to determine gender.
Popularity of O'brien since 1900
Most popular in the 1930s, when about 0.1 in every 10,000 South Africans born had the name.
* 2020–2026 so far — this decade isn’t over yet. “Per 1,000 births” compares O'brien with everyone born in the same decade in our records, so decades with more records don’t look more popular. Decades with fewer than 1,000 records are left out of that view. Includes people who have since passed away.
Show the numbers
| Decade of birth | People named O'brien | Everyone born | Per 1,000 births |
|---|---|---|---|
| 2020–2026 (so far) | 0 | 0 | — |
| 2010s | 0 | 0 | — |
| 2000s | 25 | 7,233,222 | 0.00 |
| 1990s | 22 | 9,262,591 | 0.00 |
| 1980s | 45 | 9,119,350 | 0.00 |
| 1970s | 46 | 8,269,186 | 0.01 |
| 1960s | 44 | 7,146,440 | 0.01 |
| 1950s | 35 | 5,508,070 | 0.01 |
| 1940s | 22 | 3,939,672 | 0.01 |
| 1930s | 37 | 3,121,587 | 0.01 |
| 1920s | 10 | 2,250,943 | 0.00 |
| 1910s | 3 | 1,303,466 | 0.00 |
| 1900s | 2 | 580,265 | 0.00 |
People by Age Group
| Age | All | Living |
|---|---|---|
| 20 and under | 6 | 6 |
| 21 – 40 | 67 | 66 |
| 41 – 60 | 82 | 69 |
| 61 – 80 | 71 | 55 |
| 81 – 100 | 57 | 13 |
| Over 100 | 8 | 0 |
| Date of birth unknown | 3 | 0 |
Ages are worked out from the year of birth. “Living” means no date of death is recorded.
Top 10 Surnames with O'brien
| # | Surname | People |
|---|---|---|
| 1 | Prince | 8 |
| 2 | Patience | 7 |
| 3 | Murray | 5 |
| 4 | Williams | 5 |
| 5 | De Villiers | 4 |
| 6 | Greyling | 4 |
| 7 | Kenny | 4 |
| 8 | Mullins | 4 |
| 9 | Nel | 4 |
| 10 | Smith | 4 |
Our Baby Name Generator is based on our South African records, counting every first name a person has. Only real verified South African names are used with this tool. Due to privacy restrictions, records after 2010 are not included. * Updated 21 October 2026.