Kolby vs Kollin
American parents have registered 13,001 Kolbys since 1880, against 2,782 Kollins. Kolby is still ahead, with 207 babies in 2025.
Babies given each name, 1880–2025
Kolby Kollin
Each line is every baby given the name that year, girls and boys added together — the only count that means the same thing for both names. A line breaks where the name fell below five babies in a year — the point at which the SSA stops publishing it — rather than being drawn through a figure nobody published. A single published year in a gap shows as a dot.
Who was ahead
Of the 57 years in which either name was published, Kolby for 55 years and Kollin for 2 years. The lead changed hands 2 times.
Side by side
| Kolby | Kollin | |
|---|---|---|
| Total US births | 13,001 | 2,782 |
| Most in one year | 781 | 128 |
| Babies in 2025 | 207 | 38 |
| Estimated living today | 13,000 | 2,700 |
| Median age today | 21 | 19 |
| Peak year | 2001 | 2009 |
| Best rank | 359th boys | 1,347th boys |
| Rank in 2025 | 1,222nd | 3,128th |
| First recorded | 1968 | 1970 |
| Girls / boys | 1,351 / 11,650 | 5 / 2,777 |
A rank is a position within one sex’s list for one year, so the two rank rows are not subtracted from one another and the winning column is not marked on them. The living figure is a life-table estimate, not a count.
Which name is older
Half of the Kolbys alive today are over 21; half the Kollins are over 19. That is 2 years between them: two names in use at the same time, worn by two different generations.
Where each one is strongest
- Kolby Utah (5.8×), Idaho (4.4×), Oklahoma (3.0×)
- Kollin Louisiana (5.7×), Michigan (2.9×), Texas (2.7×)
How much commoner the name is in that state than it is nationally, from births recorded since 1910.
Compare something else
Related comparisons
Social Security Administration birth records, 1880–2025, public domain. Full histories: Kolby and Kollin.