Kolby is a distinctive girls' name in United States, ranking #4074 in 1997 with 27 recorded births. The name reached its all-time peak in 2000 with 55 births ranking #2690. Since 1996, the popularity has decreased by 32.5%. In 1997, approximately 1 in every 64,469 girls born was named Kolby. STABLE Recent data shows the name is currently stable.