Meaning and history
A modern "K" respelling of Colby, an English surname derived from the Old Norse kol "charcoal" and byr "settlement," meaning roughly "charcoal town." The surname is recorded in the Domesday Book as Colebei.
20062006: 341 births, rank #669
2007: 378 births, rank #642
2008: 401 births, rank #618
2009: 371 births, rank #662
2010: 344 births, rank #684
20112011: 325 births, rank #705
2012: 286 births, rank #791
2013: 304 births, rank #749
2014: 300 births, rank #776
2015: 272 births, rank #828
20162016: 219 births, rank #950
2017: 166 births, rank #1,141
2018: 182 births, rank #1,086
2019: 153 births, rank #1,234
2020: 170 births, rank #1,144
20212021: 151 births, rank #1,262
2022: 159 births, rank #1,237
2023: 167 births, rank #1,197
2024: 156 births, rank #1,262
20252025: 165 births, rank #1,222
Kolby moved from #828 to #950 for boys between 2015 and 2016. Its highest annual birth count came in 2001, with 739 births.