Guillermo
given name · Latin script
Recorded as a male name· opposite-gender records fall within measured source noise
Guillermo is a given name written in the Latin script, with more bearers in Argentina than in any other country, where it is the 89th most common given name. In Spanish, recorded as Germanic Wilhelm, from will/wille 'will, decision' + helm 'helmet, protection': 'protected by his will'.
- ARArgentina≈1 in 301(inferred from the name graph)
- CLChile≈1 in 459
- PEPeru≈1 in 470
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.
- Argentina (inferred from the name graph)
- #430 (measured from records)
- Sources
- 473 (measured from records)
- ≈1 in 301 (inferred from the name graph)
≈150,000 people, est.
of 15M given names
Highest-authority source
Argentina, est.
measured from records inferred from the name graph
Meaning & origin(measured from records)
Germanic Wilhelm, from will/wille 'will, decision' + helm 'helmet, protection': 'protected by his will'.
Sources 1
- Diccionario etimológico de nombres propios
Attested across 14 languages in the etymology graph.
How Guillermo is read(measured from records)
Guillermo is one spelling over 2 language communities, and the dictionaries record it differently in 2 of them. Each row is what a source recorded for that language, beside the share of this name’s records the language holds. No single row is the name’s meaning.
- Spanish83%
Germanic Wilhelm, from will/wille 'will, decision' + helm 'helmet, protection': 'protected by his will'.
as a nameDiccionario etimológico de nombres propios
from the personal name Guillermo, Spanish equivalent of William.
as a nameDictionary of American Family Names
a surname originating as a patronymic, denomination from Guillaume
as a wordkaikki.org Wiktionary extract (IPA + transliterations)
- English6.3%
in Argentina. Paraguay, Uruguay
as a namePronouncing Dictionary of Proper Names
The share is ours — how much of this name’s records each language holds. The sense beside it is the source’s, quoted and credited, including where it names a gender. We do not publish a gender of our own per language: our records carry one figure for the spelling as a whole.
Where in the world(measured from records)
Guillermo 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 | ||||
|---|---|---|---|---|---|---|
| AR Argentina | #89 | ≈150,000 est. | ≈1 in 301 | 1.1K | Guillermo | 189 |
| ES Spain | #102 | 73,808 | 1 in 678 | 74K | Guillermo | 249 |
| CO Colombia | #101 | ≈71,000 est. | ≈1 in 691 | 50 | Guillermo | 185 |
| PE Peru | #58 | ≈68,000 est. | ≈1 in 470 | — | Guillermo | 137 |
| US United States | #807 | 61,844 | 1 in 5.4K | 62K | Guillermo | 473 |
| CL Chile | #52 | ≈40,000 est. | ≈1 in 459 | 120 | Guillermo | 161 |
| PY Paraguay | #981 | ≈14,000 est. | ≈1 in 517 | — | Guillermo | 60 |
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: RENAPER — Apellidos (person counts, national); Census Bureau — First Name Frequency 2020 by sex; SRCEI — Nombres más comunes (guaguas, 1920–2021); INE — Padrón per-token widgets (current living counts, given + apellidos); the co-datosgov-candidates register. 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).
Other recorded senses(measured from records)
Guillermo is also recorded in 2 other lexicons, as a different name or as an ordinary word. These are senses of the spelling, not of the name above.
From German Wilhelm or English }) William (see main dictionary).
as a nameA concise dictionary of first names
protector
as a nameDicionario Sefaradi De SobrenomesDictionary Of Sephardic Surnames Inclusive Cristaos-Novos, Conversos, Marranos, Italianos,…
Ordered by how much of this spelling's record each language holds, so a sense from a language the name is barely used in sits last rather than first.
Notable people with this name(measured from records)
- Wilhelm von Hohenzollernb. 1864DEnot in their usual nameGerman prince (1864-1927)
- Salvador Allendeb. 1908CLnot in their usual name28th president of Chile (1908–1973
- José López Portillob. 1920MXnot in their usual name58th President of Mexico
- Guillermo Vilasb. 1952ARArgentine tennis player
- Guillermo Lassob. 1955EC55th President of Ecuador from 2021 to 2023
- Guillermo Navarrob. 1955MXMexican cinematographer (1955-)
- Luis Guillermo Solísb. 1958CRCosta Rican 47th president
- Guillermo del Torob. 1964MXMexican filmmaker and author (born 1964)
- Guillermo Ochoab. 1985MXMexican association football player (born 1985)
- Juan Guillermo Cuadradob. 1988COColombian footballer
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).
Evidence(measured from records)
Attested in 78 sources across 36 countries.
| Country | Register | Year | Count | Rank |
|---|---|---|---|---|
| ES Spain | INE — Padrón per-token widgets (current living counts, given + apellidos) | — | 74K | #129 |
| ES Spain | INE — Nombres más frecuentes (Padrón Municipal) | — | 73K | #59 |
| US United States | Census Bureau — First Name Frequency 2020 by sex | 2020 | 62K | #794 |
| US United States | SSA — National Baby Names (1880–present) | 2025 | 264 | — |
| AR Argentina | RENAPER — Nombres de nacimientos (2012–present) | 2024 | 227 | #477 |
| US United States | Census Bureau — First Name Frequency 2020 by sex | 2020 | 131 | #794 |
| CL Chile | SRCEI — Nombres más comunes (guaguas, 1920–2021) | 2021 | 120 | — |
| AR Argentina | datos.gob.ar — nombres.datos.gob.ar per-name lookup (1922–2015) | 2015 | 69 | — |
| AR Argentina | RENAPER — births 1922–2015 (Kaggle mirror) | 2015 | 69 | — |
| CO Colombia | Colombia — Función Pública SIGEP II public-servant name corpus (datos.gov.co) | — | 50 | #74 |
| US United States | SSA — National Baby Names (1880–present) | 2006 | 5 | — |
Reference works 4
- Dictionary of American Family Names
- Nederlandse FamilienamenBank (Dutch surname bank; ex-Meertens Instituut, now CBG)2007
- Wikipedia given-name 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
- What are other forms of the name Guillermo?
- In the etymology graph, William, Willie and Bill are forms of the same name in other languages.
- What does the name Guillermo mean, and where does it come from?
- Germanic Wilhelm, from will/wille 'will, decision' + helm 'helmet, protection': 'protected by his will'. Recorded by Diccionario etimológico de nombres propios.
- In which country does Guillermo have the most bearers?
- Mondonomo estimates about 151 thousand people named Guillermo in Argentina, more than in any other country we hold, where it is most often spelled guillermo.
- Is Guillermo a male or female name?
- Guillermo is a male name in our records. Opposite-gender entries fall within the cross-gender noise we measure in the source data, so we don't report them as usage.
- How common is the name Guillermo?
- In Spain, the national register counted 73,808 people named Guillermo, about 1 in 678 residents.
- How common is Guillermo compared with other names?
- In Argentina, Guillermo is the 89th most common given name of 119,825 given names recorded there.
What do you want to know about Guillermo?
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/guillermoThe same 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), and bulk access is licensed separately.
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, “Guillermo” — the 89th most common given name in Argentina. Data snapshot 2026-10-10.