Koji
Meaningoften bright second son · Japanese
Koji is a Japanese boy name often meaning “bright second son”. In Japan, parents often choose a name as much for the kanji characters behind it as for its sound, so the same name can carry several shades of meaning. A meaning like this gives a child something to grow into, and a good story to tell when someone asks about their name. It sounds soft and friendly, it's easy to spell and quick to call across a playground, and it pairs well with middle names of almost any length.
Did you know?
- Scrabble scoreIf names were allowed in Scrabble, Koji would score 15 points, thanks largely to the J (worth 8).
- GenerationKoji peaked in 1984, which makes it a Millennial name. The typical Koji you'd meet today is about 41 years old. Now it's back in style, so there's a whole new generation of baby Kojis too.
- Roll callIn a typical school of 500 kids, your Koji would very likely be the only one. About 1 in 50,251 baby boys got the name in 2025.
- HistoryKoji first shows up in US birth records in 1922, the first year at least 5 babies got it. It has been in use for 103 years since.
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Popularity: U.S. Social Security Administration (babies with 5+ births per year).
About the name Koji
Koji is a boy name of Japanese origin meaning “often bright second son”. Its two syllables give it an easy rhythm, and the open vowel at the end makes it sound soft and warm. It hit its peak in the 1980s and is climbing again now. It's rarely heard today, so it stands out while still being a real, established name.
Origin:Japanese names
More Japanese boy names
- Unisex name: Asa · healer
- Unisex name: Rio · river
- Unisex name: Akari · light, brightness
- Boy name: Kenzo · often healthy third son
- Boy name: Kenji · often strong second son
- Unisex name: Ren · often lotus
- Unisex name: Zen · meditation
- Unisex name: Mars · god of war
Questions about the name Koji
What does the name Koji mean?
Koji means “often bright second son” and comes from Japanese. Other boy names with a similar meaning include Robert (“bright fame”), Arjun (“bright, shining”), Roberto (“bright fame”) and Albert (“noble and bright”).
What is the origin of the name Koji?
Koji is Japanese in origin. Other Japanese names to consider are Asa (“healer”), Rio (“river”), Akari (“light, brightness”) and Kenzo (“often healthy third son”).
Is Koji a boy or girl name?
Koji is a boy name. In 2025, 34 US boys were named Koji.
How popular is the name Koji?
Koji ranked #3,379 for US boys in 2025, given to 34 babies. Its best year was 1984, when it reached #2,613. Over the last five years it has climbed 3,241 places.
What names are similar to Koji?
If you like Koji, you might also like Robert, Arjun, Roberto and Albert.
What should I know before naming my baby Koji?
Koji is a Japanese boy name often meaning “bright second son”. In Japan, parents often choose a name as much for the kanji characters behind it as for its sound, so the same name can carry several shades of meaning. A meaning like this gives a child something to grow into, and a good story to tell when someone asks about their name. It sounds soft and friendly, it's easy to spell and quick to call across a playground, and it pairs well with middle names of almost any length. Say it out loud with your last name and any middle names you're considering, and check the initials it makes.