Ja is a distinctive boys' name in United States, ranking #11195 in 2025 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 2025, approximately 1 in every 284,679 boys born was named Ja. FALLING Recent data shows the name is currently falling.