Ja is a distinctive boys' name in United States, ranking #11392 in 2011 with 6 recorded births. The name reached its all-time peak in 1999 with 20 births ranking #3751. Since 1996, the popularity has increased by 20.0%. In 2011, approximately 1 in every 316,498 boys born was named Ja. FALLING Recent data shows the name is currently falling.