Kolby is a distinctive boys' name in United States, ranking #705 in 2011 with 325 recorded births. The name reached its all-time peak in 2001 with 739 births ranking #359. Since 1996, the popularity has increased by 33.2%. In 2011, approximately 1 in every 5,843 boys born was named Kolby. STABLE Recent data shows the name is currently stable.