Colby is a moderately popular boys' name in United States, ranking #400 in 2013 with 745 recorded births. The name reached its all-time peak in 2001 with 3,859 births ranking #99. Since 1996, the popularity has decreased by 44.6%. In 2013, approximately 1 in every 2,539 boys born was named Colby. STABLE Recent data shows the name is currently stable.
Colby is an English surname-style name with a light, approachable sound. The older place-name meaning is less central to modern use than the name's friendly, sporty feel.
Like many names of its type, Colby entered first-name use through surname tradition and later settled into mainstream naming. It has a very late twentieth-century American profile.