Koji

given name · Japanese · Latin script

Recorded as a male name· opposite-gender records fall within measured source noise

Koji is a given name, most frequently recorded in Japan, where it is the 35th most common given name. It appears chiefly in Japanese and English, written in the Latin script. Recorded meaning: Rōmaji transcription of こじ.

rarermore common
  • JPJapan1 in 879
  • USUnited States1 in 270K
  • SGSingapore1 in 99K

carrying the name, one hue, darker where it is more common. Hover a country for its figure.

≈1.6K

across 9 countries

2

recorded for this name

Sources
177

73K records

Official registry-verified

1 in 270K

United States

Spellings & scripts

KojiLatin · Japanese89K records
코지Hangul · Korean1 records

Spellings marked ● are how people bearing the name write it in our records; ○ marks a model's transliteration. Click a spelling to open its page.

Meaning & origin

Rōmaji transcription of こじ

Sources 1

  • kaikki.org Wiktionary extract (IPA + transliterations)

Attested across 15 languages in the etymology graph.

Where in the world

Sorted by bearers counted by national registers, records where none counts.

Where Koji is recorded, by country
CountryMost common spellingSources
JP Japan#3582,16866K rec.listedKoji176
US United States1,2325.8K rec.1 in 270K1.2KKoji177
CA Canada297292 rec.1Koji36
CN China25720 rec.Koji19
BR Brazil2451 rec.1 in 864K2451
GB United Kingdom244205 rec.listedKoji41
NG Nigeria124128 rec.Koji10
PH Philippines11666 rec.Koji22
SG Singapore109100 rec.Koji30
IN India7246 rec.5Koji11
RU Russia6973 rec.Koji12
TW Taiwan5016 rec.Koji19

Country figures for a list of names, at full precision, are available under licence rather than by scraping this table. How that works.

Languages

  • Japanese89K83%
  • English6.4K6%
  • Portuguese5.4K5%
  • Spanish1.1K1%
  • Hindi7221%
Show as table
Languages in which the name is recorded
NameRecordsNote
Japanese88,78383%
English6,4156%
Portuguese5,4085%
Spanish1,0991%
Hindi7221%

Language is read off each record's context, not declared by the bearer; a share is of all records for this spelling.

Other names spelled this way

Koji is also recorded as 7 other names, grouped separately because the records behind them do not connect to the one described above.

  • English given name9.5K records spelled Koji13 spellings in the group

    Most recorded in United States, Australia, Germany, Brazil

    Languages: English, German, Western Frisian

    Also written Kōji, Koeji, Kōjī, Köji, Kôji

  • Portuguese given name7.9K records spelled Koji7 spellings in the group

    Most recorded in Brazil, United States, Philippines, Argentina

    Languages: Portuguese, Spanish

    Also written Kojì, Kôji, Kōji

  • a separate given name2.2K records spelled Koji4 spellings in the group

    Most recorded in United States, India

    Also written Kōji, Kóji, Kôji

  • Hindi given name975 records spelled Koji3 spellings in the group

    Most recorded in India, United States, Singapore

    Languages: Hindi, Urdu

    Also written Kōji

  • French given name540 records spelled Koji3 spellings in the group

    Most recorded in France, United States, Singapore, Philippines

    Also written Kōji

  • Thai given name376 records spelled Koji8 spellings in the group

    Most recorded in Thailand, United States, India, Laos

    Languages: Thai, Lao

    Also written โคจิ, Khochi, โคจ, โึคจิ, Kochi

  • Indonesian given name371 records spelled Koji3 spellings in the group

    Most recorded in Indonesia, India, United States, Malaysia

    Languages: Indonesian, Malay

    Also written Kôji

45 further groups record this spelling and are not listed here.

Grouping is the name graph's, not a register's: two spellings join a group when the evidence links them, so a group is a claim about the records rather than about the people.

Other recorded senses

Koji is also recorded in 3 other lexicons, as a different name or as an ordinary word. These are senses of the spelling, not of the name above.

  • ‘Filial ruler’; ‘happy second [son)’.

    as a nameA concise dictionary of first names

  • In English, A substance that is produced by letting a mold, especially Aspergillus oryzae, grow on rice, barley, soybeans, etc., used to make fermented products such as sake, amazake, miso, and soy sauce.

    as a wordkaikki.org Wiktionary extract (IPA + transliterations)

  • In Serbo-Croatian, which, what

    as a wordkaikki.org Wiktionary extract (IPA + transliterations)

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.

Over time

01020304019401960198020002020

Show as table
Koji in SSA — National Baby Names (1880–present), United States, 1922–2025
Yearrecords
19225
19255
19266
19729
19735
19747
19756
19805
19825
198312
198418
19856
19867
19886
19896
199010
19918
199214
19945
199513
19967
19989
19997
200014
200110
200213
200314
200413
200518
200611
200717
200821
200915
201021
201114
201214
201318
201415
201517
201628
201713
201814
201915
202012
202119
202226
202333
202425
202534

US SSA — National Baby Names (1880–present)49 years between 1922–2025. One register's own figures, never a sum across registers: two registers counting the same people would double them.

Notable people with this name

1940196019802000Kōji Yakusho, b. 1956Kōji Morimoto, b. 1959Koji Kondo, b. 1961Kōji Tsujitani, b. 1962Kōji Yamamura, b. 1964Kōji Kikkawa, b. 1965Kōji Imada, b. 1966Kōji Murofushi, b. 1974Kouji Wada, b. 1974Koji Seto, b. 1988

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

Attested in 36 sources across 20 countries.

Official registers attesting Koji
CountryRegisterYearCountRank
US United StatesCensus Bureau — First Name Frequency 2020 by sex20201.2K#10,668
BR BrazilIBGE — Censo 2022 Nomes no Brasil per-token lookup (v3 API, given+surname)498#17,171
BR BrazilIBGE — names by decade (Kaggle mirror)2022245
BR BrazilIBGE — Censo 2022 Nomes no Brasil per-token lookup (v3 API, given+surname)242#21,979
BR BrazilBrasil.IO genero-nomes (IBGE Censo 2010 mirror, CC-BY-SA)237#10,394
BR BrazilIBGE — names by decade (Kaggle mirror)1960220
BR BrazilIBGE — Nomes (census name API)184#26,504
BR BrazilIBGE — names by decade (Kaggle mirror)1950150
US United StatesCensus Bureau — Surname Frequency 20202020134#131,805
US United StatesCensus Bureau — Surname Frequency 20102010109#150,452
BR BrazilIBGE — names by decade (Kaggle mirror)194089
BR BrazilIBGE — Censo 2022 Nomes no Brasil per-token lookup (v3 API, given+surname)195070

Reference works 3

  • Dictionary of American Family Names
  • Wikipedia given-name tokens
  • Wikipedia surname tokens

These works list the name; their figures are licensed and are not reproduced here.

Register rows as of the 2026-09-12 data build · 125 rows in the corpus for this spelling.

Frequently asked questions

How common is the name Koji?
We estimate roughly 1.6 thousand people bear Koji (counting its spellings and scripts) across 9 countries in our records.
In which country does Koji have the most bearers?
Koji is most frequently recorded in Japan, where it is most often spelled koji.
How common is Koji compared with other names?
In Japan, Koji is the 35th most common given name of 355,102 given names recorded there.
Is Koji a male or female name?
Koji 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.
What does the name Koji mean?
Recorded meaning: Rōmaji transcription of こじ
Query this name via API
curl https://api.mondonomo.ai/api/v1/name-graph/koji

The same payload this page is built from: spellings and scripts, countries and languages, related names, and the registers that attest the form. Rate-limited for casual use. Bulk access and licensing.

About this data

measured from records inferred from the name graph machine-generated

Data snapshot . Figures are rebuilt periodically and will change.

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, “Koji” — the 35th most common given name in Japan. Data snapshot 2026-09-12.

See how Koji parses inside a full name →