Colby
Boy name · #615 in 2025 · Rare
How old is the name Colby? In official American birth records, Colby has been tracked continuously since 1888, giving it 137 years of documented American history.
In 2025, 455 baby boys were named Colby, placing it at #615 in the official national rankings. A decade ago it stood at #456, so the name has been falling over the past ten years. Roughly one in every 3,956 boys born in 2025 was named Colby.
The 137-year story
Colby first appears in the Social Security records in 1888, when 5 boys received the name. Its peak came in 2001, when 3,859 boys were named Colby — good for #99 that year. Today's parents encounter it on its way down the popularity curve, which for many parents is exactly the appeal. Following the curve matters more than today's snapshot: a name's position on its rise-peak-decline arc is the best predictor of how common it will feel in a kindergarten class five years from now.
Babies named Colby per year. Source: Official national birth records.
Unlock the 5-year forecast and compare Colby against up to 5 other names.
Uniqueness: will there be another Colby in class?
On our rarity read — which blends how common Colby is today with its five-year momentum — the name reads as "rare". A high score means genuine rarity — your Colby will likely be the only one in the room, with the occasional spelling-out as the price.
Where Colby is most common
Geography matters for names, and Colby is no exception. Adjusted for how many boys are born in each state, Colby is most common in KS (0.8 per 1,000), KY (0.6 per 1,000), MO (0.6 per 1,000), WI (0.6 per 1,000), PA (0.5 per 1,000) — against a national average of about 0.3 per 1,000 boys. These are per-capita rates, so they show where Colby is a genuine regional favorite rather than just where the most babies are born.
Names like Colby
Statistically, parents drawn to Colby tend to be choosing among names with similar popularity arcs, era profiles, and sounds — the closest matches in our model are Kolby, Coby, Trey, Cesar, and Collin.
KolbyCobyTreyCesarCollinDevinColinAndy
Rank history (last 25 years)
| Year | Babies named Colby | Rank |
|---|---|---|
| 2025 | 455 | #615 |
| 2024 | 490 | #583 |
| 2023 | 467 | #607 |
| 2022 | 469 | #600 |
| 2021 | 420 | #651 |
| 2020 | 439 | #618 |
| 2019 | 447 | #612 |
| 2018 | 459 | #597 |
| 2017 | 465 | #584 |
| 2016 | 558 | #529 |
| 2015 | 665 | #456 |
| 2014 | 717 | #427 |
| 2013 | 746 | #400 |
| 2012 | 909 | #341 |
| 2011 | 1,026 | #314 |
| 2010 | 1,207 | #280 |
| 2009 | 1,152 | #285 |
| 2008 | 1,256 | #273 |
| 2007 | 1,221 | #283 |
| 2006 | 1,272 | #272 |
| 2005 | 1,603 | #220 |
| 2004 | 2,066 | #185 |
| 2003 | 2,170 | #181 |
| 2002 | 3,118 | #125 |
| 2001 | 3,859 | #99 |
Frequently asked questions
How old is the name Colby?
In official American birth records, the name Colby first appeared in 1888 (over 137 years ago), when 5 newborn boys received the name. It has over a century of continuous American history.
Is Colby a popular boy name?
Colby ranked #615 among boys in 2025 with 455 babies given the name — outside the top 500, making it an uncommon pick. Ten years earlier it ranked #456.
When was the name Colby most popular?
Colby peaked in 2001, when 3,859 American boys received the name (ranked #99 that year). Since 2001 the name has declined from that high.
How rare is the name Colby?
In 2025, roughly 1 in 3,956 newborn American boys was named Colby. On our rarity scale (rarity blended with momentum) we classify it as "rare".
Data source: Official American birth records, 1880–2025, national and state files. Counts reflect registered birth records for American families.