O'Brian
surname · Latin script
Recorded as a male name· opposite-gender records fall within measured source noise
/oʊˈbɹaɪən/(machine-generated) pronunciation, model-generated
O'Brian is a surname written in the Latin script, with more bearers in China than in any other country.
- USUnited States1 in 104K(measured from records)
- GBUnited Kingdom≈1 in 131K
- DMDominica1 in 19K
carrying the name, as counted by its national register where one exists and as Mondonomo estimates it elsewhere (marked ≈ and "est." on hover). One hue, darker where it is more common; hover a country for its figure.
- China (inferred from the name graph)
- Sources
- 220 (measured from records)
- 1 in 19K (inferred from the name graph)
≈25,000 people, est.
Highest-authority source
Dominica
measured from records inferred from the name graph
Spellings & scripts(measured from records)
One other spelling is counted as the same name:
Locally spelled Obrian in US United States, GB United Kingdom, NZ New Zealand and 3 more.
Spellings marked ● are how people bearing the name write it in our records, and ○ marks a model's transliteration; click a spelling to open its page.
Meaning & origin
No verified etymology recorded for this name yet — the entries below are drawn from usage statistics and the name graph.
Where in the world(measured from records)
O'Brian counted together with the spellings and other-language forms grouped with it. Where a register counted another spelling, the row names it.
Sorted by bearers: national registers' counts, and Mondonomo's estimates (≈, est.) where no register counts.
| Country | Most common spelling | Sources | |||
|---|---|---|---|---|---|
| CN China | ≈25,000 est. | ≈1 in 56K | — | Obrian | 1 |
| US United States | 3,203 | 1 in 104K | 3.3K | Obrian | 220 |
| PK Pakistan | ≈2,800 est. | ≈1 in 84K | — | Obrian | 3 |
| GB United Kingdom | ≈500 est. | ≈1 in 131K | 354 | Obrian | 65 |
| IN India | ≈310 est. | ≈1 in 4.2M | — | Obrian | 5 |
| IE Ireland | ≈84 est. | ≈1 in 61K | — | O'Brian | 16 |
| NZ New Zealand | ≈48 est. | ≈1 in 102K | — | Obrian | 7 |
| DM Dominica | 4 | 1 in 19K | 4 | — | — |
Exact figures are national registers' own counts, while figures marked ≈ and est. are Mondonomo’s estimates, counted from our sources and calibrated against those registers; hover one for how far to trust it in that country. A dash means neither exists.
Registers cited: Census Bureau — Surname Frequency 2010; Census Bureau — Surname Frequency 2000; Surnames of England and Wales (taliesin-arlein.net, Sept 2002 electoral register); Dominica — Revised List of Electors May 2025. Figures without a register are Mondonomo estimates; see Methodology.
Country figures for a list of names, at full precision, are available under licence rather than by scraping this table (how that works).
Notable people with this name(measured from records)
- Patrick O'Brianb. 1914GBnot in their usual nameEnglish novelist (1914–2000)
- Jack O'Brianb. 1914USnot in their usual nameAmerican journalist (1914-2000)
- Hugh O'Brianb. 1925USnot in their usual nameAmerican actor and United States Marine (1925–2016)
- John O'Brianb. 1944CAnot in their usual nameCanadian art historian
- Peter O'Brianb. 1947CAnot in their usual nameCanadian film producer
- Doireann Ní Bhriainb. 1952IEnot in their usual nameIrish radio producer
- Peter O'Brianb. 1956NZnot in their usual nameNew Zealand actor
- Paddy O'Brianb. 1986GBnot in their usual nameBritish pornographic actor
- Katy O'Brianb. 1989USnot in their usual nameAmerican actress, writer and martial artist
- Adam O'Brianb. 1989GBnot in their usual nameWelsh actor
The ten people covered by the most Wikipedia language editions — a proxy for cross-cultural notability, which favours historical and Western figures over equally prominent contemporary ones — shown by birth year. Source: Wikidata (CC0).
How to address them(machine-generated)
Evidence(measured from records)
Attested in 14 sources across 12 countries.
| Country | Register | Year | Count | Rank |
|---|---|---|---|---|
| GB United Kingdom | Surnames of England and Wales (taliesin-arlein.net, Sept 2002 electoral register) | 2002 | 354 | #14,618 |
| DM Dominica | Dominica — Revised List of Electors May 2025 | 2025 | 4 | #223 |
| US United States | wru Name Dictionary — US surnames, voter-file supplement (Khanna et al.) | — | — | — |
Reference works 2
- Wikipedia surname tokens
- Wikidata name items (native-script + romanized given/family names)
These works list the name; their figures are licensed and are not reproduced here.
Register rows as of the 2026-10-09 data build.
Frequently asked questions
- How do you pronounce O'Brian?
- A machine transcription gives /oʊˈbɹaɪən/ (IPA) for English.
- In which country does O'Brian have the most bearers?
- Mondonomo estimates about 25 thousand people named O'Brian in China, more than in any other country we hold, where it is most often spelled obrian.
- Where is O'Brian most common?
- Measured as a share of residents rather than as a count, O'Brian is densest in Dominica — about 1 in 19 thousand people — even though China holds more of our records for it.
- How common is the name O'Brian?
- In the United States, the national register counted 3,203 people named O'Brian in 2010, about 1 in 104 thousand residents.
What do you want to know about O'Brian?
Nobody replies to these one by one, but what readers ask decides what these pages answer next.
Query this name via API
curl -H "X-API-Key: YOUR_KEY" https://api.mondonomo.ai/api/v1/name-graph/o'brianThe payload this page is built from: spellings and scripts, countries and languages, related names, and the registers that attest the form. It takes a free API key (1,000 requests a day), which returns what this page shows everyone; the full country table, every register citation and the year-by-year series come with a licensed key, as does bulk access.
About this data
measured from records inferred from the name graph machine-generated
These figures come from the data snapshot of and will change as it is rebuilt.
Statistics are aggregated from the Mondonomo name corpus; related names and etymology are inferred from the name graph; pronunciation and any machine-marked transliterations are model-generated. Read how the numbers are made, including their known failure modes, and where the data comes from.
Reference works we consult — surname dictionaries, official name registers, Wikidata and Wiktionary — are named directly, beside the claims they support. The per-country source counts also include datasets of person records: we publish how many there are and their authority tier, but not their names.
Cite this page Mondonomo, “O'Brian”. Data snapshot 2026-10-10.