Boys' name · peaked in 2001
Colby name popularity since 1925
58,068 babies born in the US from 1925 to 2025 were named Colby (7.2% girls, 92.8% boys). Half of them were born in 2001 or earlier, so the typical Colby is about 25 years old in 2026. Colby peaked in 2001 as the #99 name for boys, and it ranked #615 in 2025.
Key facts
- US babies since 1925
- 58,068
- Named Colby, 1925–2025
- In 2025
- #615
- for boys in 2025 (455 babies)
- Girls / boys
- 92.8% boys
- 4,184 girls · 53,884 boys
- Most popular in
- Maine
- 4.46× its national share
Peak year is the year Colby made up the largest share of US boys, in records going back to 1880. Typical age is based on births from 1925 on, not on who is living today.
Colby births per year, 1925–2025
2001 was the biggest year for Colby both by count and as a share of all babies.
- Fastest rise: Between 1981 and 1986, Colby became 3.6× more common, from 1 in 7,400 baby boys to 1 in 2,070.
- Steepest fall: Between 2001 and 2006, its share of baby boys fell by 69%, from 1 in 503 to 1 in 1,620.
Shaded on the chart. Both compare Colby's share of all US boys five years apart, counting only years with at least 100 babies named Colby.
Decade by decade
Babies named Colby in each decade, and its rank among boys' names in the middle year of the decade (1935, 1945 … 2025).
| Decade | Girls | Boys | Rank |
|---|---|---|---|
| 1925–29 | 0 | 40 | – |
| 1930s | 0 | 73 | #2,418 |
| 1940s | 0 | 137 | #1,791 |
| 1950s | 65 | 225 | #1,546 |
| 1960s | 46 | 430 | #1,362 |
| 1970s | 303 | 2,754 | #413 |
| 1980s | 906 | 6,843 | #286 |
| 1990s | 1,210 | 14,261 | #209 |
| 2000s | 858 | 19,182 | #220 |
| 2010s | 475 | 7,199 | #457 |
| 2020–25 | 321 | 2,740 | #615 |
Ranks count every name given to at least 5 boys that year, so they can go past 1,000.
Generation fingerprint
48.2% of babies named Colby from 1925 to 2025 were born in the Gen Z years (1997–2012). The full split by generation:
Where Colby is most popular
The index compares Colby's share of babies in each state with its share nationwide, 1925–2025 (1.50× = 50% more common). States with at least 300 babies named Colby.
| State | Index | Babies |
|---|---|---|
| Maine | 4.46× | 1,021 |
| New Hampshire | 4.21× | 709 |
| Utah | 3.92× | 1,790 |
| Vermont | 3.86× | 345 |
| Idaho | 2.36× | 503 |
Other spellings
Spellings that sound like Colby and were given to at least 1,000 boys from 1925 to 2025, with the year each one was most popular.
| Spelling | Boys | Peak year |
|---|---|---|
| Colby (this page) | 53,884 | 2001 |
| Kolby | 11,650 | 2001 |
Names with a similar story
Of the other 1999 names on this site, these six had the share of babies closest in shape to Colby's from 1925 to 2025, however common each one got. Each line is scaled to its own high; the dashed line is Colby.
Names from the same era
Other common names that peaked within two years of Colby (2001).
Source: U.S. Social Security Administration national and state baby-name data, which covers names given to at least 5 babies of one sex in a year. About the data