Lex is a distinctive boys' name in United States, ranking #1643 in 2004 with 79 recorded births. The name reached its all-time peak in 2012 with 94 births ranking #1649. Since 1996, the popularity has increased by 276.2%. In 2004, approximately 1 in every 25,124 boys born was named Lex. FALLING Recent data shows the name is currently falling.