Dex is a distinctive boys' name in United States, ranking #3698 in 2017 with 29 recorded births. The name reached its all-time peak in 2016 with 43 births ranking #2796. Since 1996, the popularity has increased by 262.5%. In 2017, approximately 1 in every 63,804 boys born was named Dex. FALLING Recent data shows the name is currently falling.