Total births
645
Boys' name · since 1922
Koji
Koji has 645 recorded births since 1922 in federal Social Security data, most heavily in 2025 -- full year-by-year trend, decade aggregates, and state rankings follow.
- #4224
- among boys today
- 645
- born since 1922
- 2010s
- peak decade
- 70%
- more common than other boys
Yes -- Koji is the #4224 most popular boys' name in the U.S. today, with 645 recorded since 1922.
Koji has 645 recorded births among boys since 1922, per the U.S. Social Security Administration, ranked #4224 as of the latest data, more common than 70% of boys, busiest in the 2010s -- see the year-by-year trends, decade totals, and state-level distribution below, all drawn directly from SSA birth-registration files spanning 1922 to 2025.
- #4224 among boys today
- 645 born since 1922
- 2010s peak decade
- 70% more common than other boys
Data updated Jun 2026
The verdict
Koji is currently the #4224 boys' name in America, more common than 70% of boys - 645 born since 1922, peaking in the 2010s.
- #4224
- among boys today
- 645
- born since 1922
- 2010s
- peak decade
- 70%
- more common than other boys
Koji vs. every other boys name in current SSA rankings
#4224
of 14,294 boys in use
More common than 70% of names given to boys today.
2010s
Peak decade
26% of everyone ever named Koji was born in this single decade.
2025
Single peak year
34 babies were named Koji in 2025 - its busiest year on record.
How Koji compares
645 Top 38% higher than 62% of 14,294 names currently given to boys
Based on all-time total births among currently-ranked boys names. Names with fewer occurrences are grouped into wider buckets on the right.
Source U.S. Social Security Administration, national baby name data
How the numbers stack up
Koji's all-time total is 76% above the median boys name, and Liam still leads by a wide margin.
| Metric | Koji | Median boys name (Elchonon) | #1 boys name (Liam) |
|---|---|---|---|
| All-time total births | 645 | 367 | 358,536 |
| Peak-year births | 34 | 23 | 22,252 |
Koji's usage pattern, beyond the headline number
Koji splits its recorded history at 2001: 70% of all births land in the more recent half, 30% in the earlier half, a lean toward present-day use rather than a passing spike. The single quietest year was 1922 (5 births) -- compare that against the 2025 peak of 34 for a sense of just how much the name's popularity has swung.
Koji at a glance
Outside the top 1,000Peak year
2025
Current rank
#4,224
Active since
1922
Koji popularity over time
Annual U.S. births registered with the Social Security Administration · 1922–2025
- Peak year (2025)
- 34
- Annual births at peak, across 104 years of records
Koji by decade
Total births in each ten-year window, peak vs trough at a glance
2010s was Koji's strongest decade.
169 babies received the name during that ten-year window, about 26% of all-time use.
Koji births by decade
Total births in each ten-year window
- 1920s 16
1920s
16 births
- 1970s 27
1970s
27 births
- 1980s 65
1980s
65 births
- 1990s
1990s
73 births
- 2000s
2000s
146 births
- 2010s
2010s
169 births
- 2020s
2020s
149 births
What this shows Peak: 2010s at 169 births (26% of all-time use).
How Koji compares to similarly-sized names
Years in SSA records vs. share of all-time use concentrated in the single peak year, among 15 boys names closest to Koji's total volume
Koji vs 15 similarly-sized boys names
Koji by state
Where Koji concentrates geographically, total births since 1922
| Rank | State | Visual share | Births | Share of total |
|---|---|---|---|---|
| #1 | California | | 142 | 22.0% |
| #2 | Hawaii | | 5 | 0.8% |
| #3 | Washington | | 5 | 0.8% |
California share of Koji's total US births 22.0%
Even split
142 of 645 births nationwide. Compared to a flat distribution across 3 reporting states.
Frequently Asked Questions
How popular is the name Koji? ▼
645 babies have been named Koji since 1922. It currently ranks #4224 among boys. The peak year was 2025 with 34 births.
When was Koji most popular? ▼
Koji was most popular in the 2010s decade with 169 total births. The single peak year was 2025.
Where is Koji most popular? ▼
The top states for the name Koji are California (142 births), Hawaii (5 births), Washington (5 births).
How long has the name Koji been used? ▼
Koji has been recorded in Social Security data since 1922, spanning 104 years of data through 2025.
What names are similar to Koji? ▼
Names with a similar sound or spelling include Kojo, Kojak, Kojiro. These share a common prefix and are also used for boys.
What to do with Koji's data
- Koji's usage has stayed within range of its 2010s decade-level peak (169 total births) through the 2020s (149) -- a comparatively stable name, not a fading trend.
- California records the most Kojis (142 births) -- see the full state breakdown if geography matters to your decision. California names
- Weighing it against an alternative? Put two names side by side. Compare names
Figures reflect SSA-reported births only; see the methodology above for the privacy-suppression floor.
Keep exploring Koji
Nearby Names Like Koji
Names with a similar sound, spelling, or feel to Koji
Compare Koji side by side: Koji vs Kojo Koji vs Kojak Koji vs Kojiro
Related Names
Names with a similar popularity rank to Koji
Data Sources
Data as of June 2026. Source: U.S. Social Security Administration (SSA).
According to the Social Security Administration, this profile draws directly from the agency's public-use baby-name files (updated June 2026). See our methodology for the full extraction, aggregation, and privacy-suppression rules.
Primary: Source: U.S. Social Security Administration, Baby Names from Social Security Card Applications, National Data, 1922–2025 (ssa.gov/oact/babynames).
State-level: Source: U.S. Social Security Administration, Baby Names, State-Level Files (namesbystate.zip).
Cite this page
NameAlmanac Editorial. "Koji: #4224 Boys' Name - 645 Births, Peak 2025." NameAlmanac. Accessed via https://namealmanac.com/name/koji. Licensed CC BY-SA 4.0.
Name Almanac is rendered directly from the Social Security Administration's public baby-name files, no number is typed in by an editor. This profile for Koji draws directly on SSA national and state-level files, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of June 2026.