Kolby is a distinctive boys' name in United States, ranking #828 in 2015 with 272 recorded births. The name reached its all-time peak in 2001 with 739 births ranking #359. Since 1996, the popularity has increased by 11.5%. In 2015, approximately 1 in every 7,045 boys born was named Kolby. STABLE Recent data shows the name is currently stable.