Coby is a moderately popular boys' name in England & Wales, ranking #371 in 2008 with 101 recorded births. The name reached its all-time peak in 2019 with 213 births ranking #236. Since 1996, the popularity has increased by 531.3%. In 2008, approximately 1 in every 3,360 boys born was named Coby. STABLE Recent data shows the name is currently stable.
Coby is a compact English short form of Jacob. That gives it a much clearer source line than the earlier broad discussion of several overlapping variant families.
As a nickname-style form, Coby works because it sounds casual and familiar while still resting on a major biblical classic. Its modern use is more flexible, but the Jacob connection is the clearest core route.