Kolby is a distinctive boys' name in United States, ranking #1237 in 2019 with 153 recorded births. The name reached its all-time peak in 2001 with 739 births ranking #359. Since 1996, the popularity has decreased by 37.3%. In 2019, approximately 1 in every 11,721 boys born was named Kolby. STABLE Recent data shows the name is currently stable.